MASARU SUZUKI
| Division of General Education（Graduate School of Informatics and Engineering） | Professor |
| Division of General Education（School of Informatics and Engineering ） | Professor |
| Institute for Advanced Science | Professor |
| Coordinated Center for UEC Research Facilities | Professor |
| Department of Engineering Science | Professor |
| Cluster III (Fundamental Science and Engineering) | Professor |
| Nanotribology Research Center | Professor |
Researcher Information
Research Keyword
Educational Background
Research Activity Information
Paper
- Simultaneous Measurements of 4He Confined in an Oriented Porous Membrane by 32 and 100 kHz Tuning Forks
Airi Kaneko; Junko Taniguchi; Masaru Suzuki; Mitsunori Hieda
Proceedings of the 29th International Conference on Low Temperature Physics (LT29), Journal of the Physical Society of Japan, 38, 011005, 22 May 2023, Peer-reviwed
International conference proceedings, English - Engineering nonlinear optical phenomena by arbitrarily manupulating the phase relationship amang the relevant optical fields
W. Liu; C. Ohahe; J. Zheng; M. Suzuki; K. Minoshima; H. Ogawa; T. Takano; M. Katsuragawa
Communications Physics, 5, 179-1-8, 2022, Peer-reviwed
Scientific journal, English - Structural Study of Adsorbed Helium Films: New Approach with Synchrotron Radiation X‑rays
Akira Yamaguchi; Hiroo Tajiri; Atsuki Kumashita; · Jun Usami; Y. Yamane·; A. Sumiyama; M. Suzuki; T. Minoguchi; Y. Sakurai; H. Fukuyama
J. Low Temp. Phys., Springer Science and Business Media LLC, 208, 5-6, 441-448, 2022, Peer-reviwed
Scientific journal, English - Effects of 3He impurities on the mass decoupling of 4He films
K. Ishibashi; J. Hiraide; J. Taniguchi; T. Minoguchi; M. Suzuki
Physical Review B, 102, 104104-1-6, 2020, Peer-reviwed
Scientific journal, English - Possible Thermodynamical Phase Slips in Superfluid 4He Confined in a 2.5-nm Channel of FSM
J. Taniguchi; K. Taniguchi; K. Kanno; M. Suzuki
Jounal of Low Temperature Physics, 201, 139-145, 2020, Peer-reviwed
Scientific journal, English - Ultrasound study of the mass decoupling of 4He inert films on mesoporous silica
J. Taniguchi; H. Ichida; M. Suzuki
Physical Review B, 99, 024112-1,4 (2019)., 99, 024112-1--4, 2019, Peer-reviwed
Scientific journal, English - Optical technology for arbitrarily manipulating amplitudes and phases of coaxially propagating highly discrete spectra
C. Zhang; K. Yoshii; D. Tregubov; C. Ohae; J. Zheng; M. Suzuki; K. Minoshima; M. Katsuragawa
Physical Review A, 100, 53836-1-10, 2019, Peer-reviwed
Scientific journal, English - Reentrant pinning of a 3He overlayer in a 3He-4He mixture film
K Okamura; J. Taniguchi; M. Hieda; M. Suzuki
Physical Review B, 100, 214508-1-4, 2019, Peer-reviwed
Scientific journal, English - Superlubrication by phonon confinement
Noriyuki Wada; Makoto Ishikawa; Takuma Shiga; Junichiro Shiomi; Masaru Suzuki; Kouji Miura
Physical Review B, American Physical Society, 97, 16, 161403(R)-1-5, 18 Apr. 2018, Peer-reviwed, The superlubrication described here, involving confined phonons, is easily achievable and very simple because it uses only submicron islands, smaller than the mean free path of the phonons, to confine phonons. We can achieve superlubrication with a friction force of piconewton order at the submicron island. We can call this phononic lubrication or self-lubrication because phonons induced by tip shearing are confined within the submicron islands and decrease the friction during the subsequent sliding. Phonon confinement should make it possible to directly develop applications for lubricants and ultimately to open a novel avenue of tribology.
Scientific journal, English - Tailored Raman-resonant four-wave-mixing processes
C. Ohae; J. Zheng; K. Ito; M. Suzuki; K. Minoshima; M. Katsuragawa
Optics Express, OSA - The Optical Society, 26, 2, 1452-1460, 22 Jan. 2018, Peer-reviwed, Nonlinear optical processes are strongly dominated by phase relationships among electromagnetic fields involved. In this paper, we theoretically and experimentally show that in a Raman-resonant four-wave-mixing process, the first anti-Stokes and Stokes generations can be tailored in a variety of ways by manipulating the phase relationships among the relevant electromagnetic fields.
Scientific journal, English - Torsional Oscillator Measurements, of Liquid 4He Confined in 2.5-nm Channel of FSM
K. Taniguchi; J. Taniguchi; M. Suzuki
Journal of Physics: Conference Series, 696, 012005-1-5, 2018, Peer-reviwed
International conference proceedings, English - Decoupling of Solid 4He layers under the Superfluid Overlayer
K. Ishibashi; J. Hiraide; J. Taniguchi; M. Suzuki
Journal of Physics: Conference Series, 969, 012011-1-5, 2018, Peer-reviwed
International conference proceedings, English - Twofold Torsional Oscillator Experiments from Film to Pressurized Liquid He-4 in a Nanometer-Size Channel
Kenta Demura; Junko Taniguchi; Masaru Suzuki
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, PHYSICAL SOC JAPAN, 86, 11, 114601-1,-5, Nov. 2017, Peer-reviwed, We measured the superfluid response of He-4 in a one-dimensional channel of 2.8 nm in diameter under unsaturated vapor pressure using a twofold torsional oscillator, and studied whether or not the superfluid response can be explained by the present Tomonaga-Luttinger (TL) liquid model down to the film region. For this system, the superfluid response is accompanied by a large dissipation throughout the film and liquid regions. We observed that the temperature of the dissipation peak is decreased by lowering the measuring frequency from 2 to 0.5 kHz, for a dilute liquid under unsaturated vapor pressure. Furthermore, the decrease becomes small with decreasing density from the pressurized to dilute liquid. On the other hand, no change in the dissipation peak temperature was observed in the film. The results show that, at least down to the liquid under unsaturated vapor pressure, the superfluid response can be explained by the TL liquid model. The dissipation peak itself varies continuously from the thin film to the pressurized liquid He-4. This indicates that the dissipation in the film has the same origin as the liquid, in spite of the lack of a shift in the dissipation peak temperature shift with the measuring frequency.
Scientific journal, English - Tailored nonlinear optical process by manipulating the relative phases among the relevant electromagnetic fields
C. Ohae; J. Zheng; K. Ito; M. Suzuki; K. Minoshima; M. Katsuragawa
Optics InfoBase Conference Papers, OSA - The Optical Society, 2017, 2017, Peer-reviwed, We describe tailoring nonlinear optical process by manipulating the spectral phases among the relevant electromagnetic fields. We demonstrate, as a typical example, an efficient generation of Stokes or anti-Stokes component in the Raman-resonant four-wave-mixing process.
International conference proceedings, English - Experimental observation of phonon generation and propagation at a MoS2(0001) surface in the friction process
Makoto Ishikawa; Noriyuki Wada; Takahiko Miyakawa; Hiroshi Matsukawa; Masaru Suzuki; Naruo Sasaki; Kouji Miura
PHYSICAL REVIEW B, AMER PHYSICAL SOC, 93, 20, 201401-1,-4, May 2016, Peer-reviwed, We report phonon dispersion curves obtained at a MoS2(0001) surface in the friction process with a load and shear. An atomic force microscope tip used to apply stresses generated lattice strain on an oscillating MoS2(0001) surface, which dissipated via acoustic phonons. The dissipation energy of the phonons strongly depended on the size of the lattice strain. The motion of the acoustic phonons consisted of a longitudinal mode and a transverse mode, but the occurrence of their phonon modes depended on the crystallographic direction, which reflects the atomic arrangement of the MoS2(0001) surface. Thus, we can control the energy dissipation and friction by using the phonon dissipation curves in the friction process with a load and shear.
Scientific journal, English - Elementary process of nanoscale friction of superlubric C60 molecular bearings
Ogawa Ryouta; Itamura Noriaki; Suzuki Masaru; Miura Kouji; Sasaki Naruo
Abstract of annual meeting of the Surface Science of Japan, The Surface Science Society of Japan, 36, 155-155, 2016, 超潤滑C60分子ベアリング（グラフェン/C60/グラフェン界面構造）の分子力学シミュレーションを行い、上層グラフェンの走査過程のナノスケール摩擦のメカニズムを議論する。上層グラフェンをC60分子の六員環との格子整合性の良い方向に走査すると、C60分子のスティック・スリップ運動が周期的に生じる。特にスリップ運動前後の全ポテンシャルエネルギー面の変化に着目して、エネルギー散逸の素過程を明らかにする。
Japanese - Nano-sliding of an AFM tip on the graphite substrate using a tuning fork crystal resonator
Suzuki T.; Tanahara S.; Taniguti J.; Suzuki M.; Sasaki N.; Ishikawa M.; Miura K.
Meeting Abstracts of the Physical Society of Japan, The Physical Society of Japan, 71, 2392-2392, 2016,我々は原子間力顕微鏡(AFM)探針と水晶マイクロバランス(QCM)を組み合わせた装置を開発し、ナノすべり摩擦の測定を行ってきた。この測定では摩擦によるエネルギー散逸をQ値の変化として得ることができる。本研究では音叉型水晶振動子を用いたグラファイト基板のナノすべり摩擦測定を報告する。
Japanese - Temperature dependence of the nano-sliding friction of graphite surface
Kobayashi T.; Oyamada T.; Taniguchi J.; Suzuki M.; Sasaki N.; Ishikawa M.; Miura K.
Meeting Abstracts of the Physical Society of Japan, The Physical Society of Japan, 71, 2393-2393, 2016,我々は原子間力顕微鏡(AFM)探針と水晶マイクロバランス(QCM)を組み合わせた装置を開発し，ナノすべり摩擦の測定を行ってきた。この測定では摩擦によるエネルギー散逸をQ値の変化として得ることができる。本研究では温度を変化させ，グラファイト表面のナノすべり摩擦測定を報告する。
Japanese - Phonon Dispersion in the Friction Procces at MoS2(0001) Surface Dot
Wada N; Ishikawa M; Suzuki M; Sasaki N; Miura K
Meeting Abstracts of the Physical Society of Japan, The Physical Society of Japan, 71, 2421-2421, 2016,MoS_2_(0001)基盤を水晶振動子電極上に接着し、任意の振幅で水平に振動させる。振動しているMoS_2_(0001)基盤をAFMの探針で押し、MoS_2_(0001)基板表面と探針先端の接触部での散逸エネルギーを水晶振動子の振幅の減衰量から見積もった。この際、MoS_2_(0001)表面上にドットを形成し、測定を行ったところ探針との摩擦によりフォノンが生まれ、分散していることが分かった。
Japanese - Dynamical Superfluid Response of He-3-He-4 Solutions Confined in a Nanometer-Size Channel
Kenta Demura; Junko Taniguchi; Masaru Suzuki
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, PHYSICAL SOC JAPAN, 84, 9, 09406-1,-5, Sep. 2015, Peer-reviwed, We measured the superfluid response of dilute He-3-He-4 solutions confined in a one-dimensional channel of 2.8 nm in diameter using a twofold torsional oscillator. We prepared three He-3 concentrations of 0.0, 2.0, and 4.0 at. %, and found that the response of 4.0 at.% decreases by 70mK at 0.13 MPa from that of liquid He-4. The decrease does not depend strongly on the pressure and is proportional to the He-3 concentration. Furthermore, we found the measurement frequency dependence in the same manner as for liquid He-4. The response of 4.0 at.% at a measurement frequency of 0.5 kHz at 0.13 MPa is suppressed by about 40mK from 2 kHz, and the magnitude of the suppression does not depend strongly on both the 3He concentration and the pressure.
Scientific journal, English - Dynamic friction of nanoscale sliding on a C<inf>60</inf> deposited film
Yuka Ikada; Shohei Tanahara; Tomohiro Oyamada; Daisuke Inoue; Shingo Machida; Junko Taniguchi; Masaru Suzuki; Makoto Ishikawa; Kouji Miura
e-Journal of Surface Science and Nanotechnology, Surface Science Society of Japan, 13, 135-138, 2015, Peer-reviwed, We measured the frictional behavior acting on C<
inf>
60<
/inf>
films at a small normal load as a function of oscillation amplitude using a MHz-range quartz crystal resonator and an optical AFM cantilever. The frictional behavior for C<
inf>
60<
/inf>
films varies by the amplitude: For the amplitudes smaller than the C-C bond length of the C<
inf>
60<
/inf>
molecule, the dynamic frictional force is directly proportional to the amplitude, while it becomes almost constant for larger amplitudes. Although the observation is in qualitatively the same manner as HOPG, the dynamic frictional force for small amplitudes is significantly larger than that of HOPG. This difference suggests that C<
inf>
60<
/inf>
molecules easily tilt and/or rotate when the tip slides in C<
inf>
60<
/inf>
films, and the dynamic friction arises from the tilting and/or rotating motion.
International conference proceedings, English - Friction and stiffness surface image using a quartz crystal microbalance
Shohei Tanahara; Daisuke Inoue; Shingo Machida; Yuka Ikada; Junko Taniguchi; Masaru Suzuki; Makoto Ishikawa; Kouji Miura
e-Journal of Surface Science and Nanotechnology, Surface Science Society of Japan, 13, 164-166, 2015, Peer-reviwed, We carried out the surface mapping of the dynamic friction and the effective elastic stiffness of contact by using a quartz crystal resonator and an AFM cantilever, associated with the topographic image. The tip was scanned across the Au substrate on the resonator in the constant-height mode. A typical grain structure of the Au substrate in the dynamic friction and the effective stiffness images was observed, simultaneously with the topographical image. This technique enables us to observe the surface properties related to contact in the nanometer scale.
International conference proceedings, English - Evidence for a Common Physical Origin of the Landau and BEC Theories of Superfluidity
S. O. Diallo; R. T. Azuah; D. L. Abernathy; Junko Taniguchi; Masaru Suzuki; Jacques Bossy; N. Mulders; H. R. Glyde
PHYSICAL REVIEW LETTERS, AMER PHYSICAL SOC, 113, 21, 215302-1,-5, Nov. 2014, Peer-reviwed, There are two renowned theories of superfluidity in liquid He-4, quite different and each with specific domains of application. In the first, the Landau theory, superflow follows from the existence of a well-defined collective mode supported by dense liquid He-4, the phonon-roton mode. In the second, superflow is a manifestation of Bose-Einstein condensation (BEC) and phase coherence in the liquid. We present combined measurements of superfluidity, BEC and phonon-roton (P-R) modes in liquid He-4 confined in the porous medium MCM-41. The results integrate the two theories by showing that well-defined P-R modes exist where there is BEC. The two are common properties of a Bose condensed liquid and either can be used as a basis of a theory of superfluidity. In addition, the confinement and disorder suppresses the critical temperature for superfluidity, T-c, below that for BEC creating a localized BEC "phase" consisting of islands of BEC and P-R modes. This phase is much like the pseudogap phase in the cuprate superconductors.
Scientific journal, English - Competition Between the Superfluid Overlayer and the Mobile Solid Layer of He-3-He-4 Mixture Films on Porous Gold
Junko Taniguchi; Toshio Mouri; Masaru Suzuki; Mitsunori Hieda; Tomoki Minoguchi
JOURNAL OF LOW TEMPERATURE PHYSICS, SPRINGER/PLENUM PUBLISHERS, 175, 1-2, 414-419, Apr. 2014, Peer-reviwed, In the previous quartz crystal microbalance measurements for He-4 films adsorbed on porous gold, we have observed a competition between superfluidity and slippage: In low areal densities, the resonance frequency increases gradually below T (S) due to the slippage of solid layer, while at high areal densities the slippage disappears and the superfluid onset of liquid overlayer is observed at T (C) . In the crossover region, the slippage below T (S) is suddenly suppressed at T (D) , which is much lower than T (C) . In the present work, we introduced a small amount of He-3 onto He-4 films, and studied the competition as a function of He-3 areal density rho (3). As rho (3) is increased, T (C) is monotonically lowered. In contrast, T (D) increases up to a certain value of rho (3), and then turns over to decrease in parallel to T (C) .
Scientific journal, English - Path Integral Calculation of He-4 in One-Dimensional Channel Model
Hajime Kiriyama; Junko Taniguchi; Masaru Suzuki; Takeo Takagi
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, PHYSICAL SOC JAPAN, 83, 4, 0446019-1,-4, Apr. 2014, Peer-reviwed, We consider He-4 particles confined in a nanoscale quasi-one-dimensional channel in the liquid density range and numerically calculate the total energy per particle and the superfluid fraction by an imaginary time path integral Monte Carlo method. T-BEC at which the total energy drops owing to particle exchange, shifts to a lower value with decreasing channel diameter, and disappears below a diameter of 0.48 nm. It was found that T-BEC is close to the superfluid onset temperature observed in the torsional oscillator experiment. In addition, the superfluid fraction along the channel grows slowly below T-BEC. Its magnitude decreases with increasing channel length, and the superfluid coherence in terms of thermodynamics disappears in infinitely long channels.
Scientific journal, English - Nuclear magnetic resonance on He-3 confined in 2.8-nm channel of FSM16
Junko Taniguchi; Daiki Tanaka; Masaru Suzuki
27TH INTERNATIONAL CONFERENCE ON LOW TEMPERATURE PHYSICS (LT27), PTS 1-5, IOP PUBLISHING LTD, 568, 2014, Peer-reviwed, We have performed continuous-wave (cw) nuclear magnetic resonance measurements for He-3 confined in 2.8-nm channel of FSM16. The magnetization shows a reduction from the Curie law at low temperature for the high areal density where He-3 in the channel consists of three portions; a solid first-layer, an amorphous-solid overlayer, and a fluid inside. By an analysis for the magnetization and the available heat capacity data, the reduction can be attributed to an interaction of spins in amorphous solid and a degenerate of fluid.
International conference proceedings, English - Managing the Learning Quality in Physics by e-Learning Inprovement with Collaborative Education
M. Kanenaga; M. Suzuki; K. Abe; J. Nakamura; T. Takada; N. Kokubo; Y. Fuseya
JPS Conf. Proc., 1, 017018-1,-4, 2014
International conference proceedings, English - Physics Laboratory in UEC
T. Takada; J. Nakamura; M. Suzuki
JPS Conf. Proc., 1, 017031-1,-4, 2014, Peer-reviwed
International conference proceedings, English - Dynamical superfluid response of He-4 confined in a nanometer-size channel
Junko Taniguchi; Kenta Demura; Masaru Suzuki
PHYSICAL REVIEW B, AMER PHYSICAL SOC, 88, 1, 014502-1,-4, Jul. 2013, Peer-reviwed, We have studied the superfluid response of liquid He-4 confined in a one-dimensional nanometer-size channel by means of a twofold torsional oscillator at 2000 and 500 Hz. For the lower-frequency mode, both the superfluid onset and the dissipation peak shift to the low-temperature side by 40 mK under 0.13 MPa, and the shift is slightly enhanced by the application of pressure. The strong frequency dependence indicates that the superfluid response is a dynamical phenomenon. Furthermore, this dependence is consistent with the theoretical prediction based on the Tomonaga-Luttinger liquid model.
Scientific journal, English - Slippage of 4He films and precursor phenomenon of superfluidity
Kei Noda; Ko Okamura; Junko Taniguchi; Masaru Suzuki; Mitsunori Hieda
Journal of Low Temperature Physics, 171, 5-6, 638-643, Jun. 2013, Peer-reviwed, We have carried out quartz crystal microbalance (QCM) experiments for 4He films on an exfoliated single-crystalline graphite using a 32 kHz tuning fork, and have measured the temperature dependence of the resonance frequency and the Q value for various areal densities and oscillation amplitudes. Comparing with the previous experiments for Grafoil, the decoupling of the films due to the slippage or the superfluidity was larger than that of Grafoil, and the competition between the slippage and the superfluidity was observed in three-atom thick films. Furthermore, it was found that the slippage is suppressed gradually at higher temperature than the superfluid onset T c, and that the relaxation time decreases at low temperatures while it obeys the Arrhenius law at high temperatures. These results suggest a precursor to the superfluidity of 4He films. © 2013 Springer Science+Business Media New York.
Scientific journal, English - Double torsional oscillator measurements for 4He confined in 1D nano-porous medium FSM16 with a 2.8-nm channel
J. Taniguchi; K. Demura; M. Suzuki
Journal of Low Temperature Physics, 171, 5-6, 644-649, Jun. 2013, Peer-reviwed, We have studied the frequency dependence of superfluid response for 4He confined in a one-dimension nano-porous medium, FSM16, with 2.8-nm channel. The measurements were performed for an identical sample at two frequencies of 2000 and 500 Hz, by means of a double torsional oscillator. It was made clear that the rapid growth of superfluid response for the low frequency mode occurs at several tens mK lower than those for the high frequency mode. The difference between the two frequency modes is enhanced by the application of pressure. The observed frequency dependence suggests a dynamical superfluid peculiar to one dimension. © 2012 Springer Science+Business Media, LLC.
Scientific journal, English - Double torsional oscillator measurements for 4He confined in 1D nano-porous medium FSM16 with a 2.8-nm channel
J. Taniguchi; K. Demura; M. Suzuki
Journal of Low Temperature Physics, 171, 5-6, 644-649, Jun. 2013, Peer-reviwed, We have studied the frequency dependence of superfluid response for 4He confined in a one-dimension nano-porous medium, FSM16, with 2.8-nm channel. The measurements were performed for an identical sample at two frequencies of 2000 and 500 Hz, by means of a double torsional oscillator. It was made clear that the rapid growth of superfluid response for the low frequency mode occurs at several tens mK lower than those for the high frequency mode. The difference between the two frequency modes is enhanced by the application of pressure. The observed frequency dependence suggests a dynamical superfluid peculiar to one dimension. © 2012 Springer Science+Business Media, LLC.
Scientific journal, English - Dynamical frictional force of nanoscale sliding
Daisuke Inoue; Shingo Machida; Junko Taniguchi; Masaru Suzuki; Makoto Ishikawa; Kouji Miura
PHYSICAL REVIEW B, AMER PHYSICAL SOC, 86, 11, 115411-1,-4, Sep. 2012, Peer-reviwed, We measured the dynamical frictional force acting on highly oriented pyrolytic graphite and C-60 substrates by a sliding Si3N4 tip as a function of sliding distance using the probe-tip-quartz-crystal-resonator technique. It was found that the dynamical frictional force undergoes a drastic change when the oscillation amplitude is approximately the lattice constant of each substrate: For a small case, it is directly proportional to the amplitude, while for a large case, it does not depend on the amplitude. The observed behavior is qualitatively understood by a simple one-dimensional Tomlinson model.
Scientific journal, English - Dynamic friction of nano-sliding between graphite
Daisuke Inoue; Junko Taniguchi; Masaru Suzuki; Makoto Ishikawa; Kouji Miura
e-Journal of Surface Science and Nanotechnology, 10, 100-102, 14 Apr. 2012, Peer-reviwed, We measured the dynamic friction of nano-sliding between graphite surfaces using a new apparatus. This apparatus enables us to obtain the frictional force of nano-sliding down to a sub-atomic distance. For large sliding distances above 0.68 nm, it was found that the frictional force, i.e., the energy dissipation per distance, is constant. In contrast, for small sliding distances below 0.68 nm, this force was proportional to distance. From these observations, we can conclude that the mechanism of dynamic friction undergoes a drastic change when the sliding distance becomes smaller than the lattice constant. © 2012 The Surface Science Society of Japan.
International conference proceedings, English - Dynamic friction of nano-sliding between graphite
Daisuke Inoue; Junko Taniguchi; Masaru Suzuki; Makoto Ishikawa; Kouji Miura
e-Journal of Surface Science and Nanotechnology, 10, 100-102, 14 Apr. 2012, Peer-reviwed, We measured the dynamic friction of nano-sliding between graphite surfaces using a new apparatus. This apparatus enables us to obtain the frictional force of nano-sliding down to a sub-atomic distance. For large sliding distances above 0.68 nm, it was found that the frictional force, i.e., the energy dissipation per distance, is constant. In contrast, for small sliding distances below 0.68 nm, this force was proportional to distance. From these observations, we can conclude that the mechanism of dynamic friction undergoes a drastic change when the sliding distance becomes smaller than the lattice constant. © 2012 The Surface Science Society of Japan.
International conference proceedings, English - Phonon excitation for He-4 confined in nanometer-size uniform channel under pressure
Junko Taniguchi; Masaru Suzuki
26TH INTERNATIONAL CONFERENCE ON LOW TEMPERATURE PHYSICS (LT26), PTS 1-5, IOP PUBLISHING LTD, 400, 2012, Peer-reviwed, We have studied the heat capacity of pressurized He-4 confined in the honeycomb structure of a nanometer-size uniform straight channel at low temperature. The temperature (T) dependence is almost in proportion to T-3 between 0.4 and 0.7 K, and a slight deviation from the T-3-dependence appears below this temperature region. The deviation is possibly explained by the beginning of the crossover to the one-dimensional (1D) phonon state which is continuous in the axial direction, from the 3D-like state with the excitation to discrete energy levels in the cross section
International conference proceedings, English - Mechanical response of noble gas films to an oscillating substrate
Hajime Kobayashi; Junko Taniguchi; Masaru Suzuki; Kouji Miura; Ichiro Arakawa
26TH INTERNATIONAL CONFERENCE ON LOW TEMPERATURE PHYSICS (LT26), PTS 1-5, IOP PUBLISHING LTD, 400, 012034-1,-5, 2012, Peer-reviwed, We carried out quartz-crystal microbalance (QCM) experiments for Xe films adsorbed on an exfoliated single-crystalline graphite substrate (Xe/Gr) and Kr films adsorbed on a synthetic mica substrate (Kr/mica) around LN2 temperature. For Xe/Gr, it was found that the resonance frequency decreases greatly around the first layer completion, while it does not decrease at low coverages. The observed behavior is similar to that of Kr films on a graphite substrate (Kr/Gr). This demonstrates that the layer completion strongly affects the sliding motion of noble gas films on graphite.
International conference proceedings, English - Mechanical response of He-4 films adsorbed on single-crystalline graphite
Kei Noda; Fumikazu Nihei; Hajime Kobayashi; Junko Taniguchi; Masaru Suzuki
26TH INTERNATIONAL CONFERENCE ON LOW TEMPERATURE PHYSICS (LT26), PTS 1-5, IOP PUBLISHING LTD, 400, 012056-1,-4, 2012, Peer-reviwed, We carried out quartz crystal microbalance (QCM) experiments of a 32 kHz quartz tuning fork for He-4 films adsorbed on exfoliated single-crystalline graphite, and measured the temperature dependence of the resonance frequency and Q value for various areal densities. To study the sliding direction dependence, two quartz tuning forks oscillating in the different crystal directions were prepared. It was found that the resonance frequency does not decrease greatly in the monolayer region, and the decoupling from the oscillating substrate is enhanced compared with Grafoil. We observed, however, a weak decrease in frequency around the commensurate phase of monolayer, and this decrease shows the sliding direction dependence.
International conference proceedings, English - Anomalous suppression of superfluidity for He-4 in Gelsil glass
Kouetsu Mikami; Toshiaki Kobayashi; Junko Taniguchi; Masaru Suzuki; Keiya Shirahama
26TH INTERNATIONAL CONFERENCE ON LOW TEMPERATURE PHYSICS (LT26), PTS 1-5, IOP PUBLISHING LTD, 400, 012048-1,-4, 2012, Peer-reviwed, We have studied the superfluid behavior of liquid He-4 confined in three samples of Gelsil glass, whose pore size distribution was examined by measuring N-2 pressure isotherm. It was found that the superfluid transition temperature under the saturation vapor pressure is 1.37 K for one of the samples whose pore size ranges up to around 6 nm, while it is 0.83 K for another one in which the distribution of pore size is small above 4 nm. Both of the samples have a bottle-neck structure of the same size. These results demonstrate that the suppression of superfluidity is related to the pore size distribution rather than the size of the neck.
International conference proceedings, English - Superfluidity and BEC of liquid He-4 confined in a nanometer-size channel
Junko Taniguchi; Rina Fujii; Masaru Suzuki
PHYSICAL REVIEW B, AMER PHYSICAL SOC, 84, 13, 134511-1,-5, Oct. 2011, Peer-reviwed, We have studied the heat capacity and superfluidity of liquid He-4 confined in a uniform and straight nanometer-size channel. The heat capacity of liquid He-4 in the channel has a bend at a certain temperature T-B; below this temperature a small amount of the superfluid fraction appears. This means that He-4 atoms enter a BEC-like low-entropy state below T-B. Additionally, the superfluid fraction showed a second growth far below T-B under low pressure, accompanied by the dissipation. This two-stage growth is possibly a feature of the quasi-one-dimensional system.
Scientific journal, English - Solidification of He-4 confined in a nanometer-size channel
Junko Taniguchi; Masaru Suzuki
PHYSICAL REVIEW B, AMER PHYSICAL SOC, 84, 5, 054511-1,-6, Aug. 2011, Peer-reviwed, Solidification of He-4 confined in a one-dimensional 2.8-nm channel of FSM was studied by pressure and heat capacity measurements. It was found that the freezing pressure in the channel is greatly elevated and is between 3.3 and 3.8 MPa at absolute zero. Furthermore, the density change at the liquid-solid transition is evaluated. The decrease in the molar volume is less than 1 x 10(-2) cm(3)/mol at the transition of 4 MPa, which is about two orders of magnitude smaller than that of bulk. From this observation, we can conclude that solid He-4 confined in the channel has a density as low as liquid.
Scientific journal, English - Path Integral Calculation of He-4 in Quasi-one-dimensional Channels
H. Kiriyama; J. Taniguchi; M. Suzuki; T. Takagi
JOURNAL OF LOW TEMPERATURE PHYSICS, SPRINGER/PLENUM PUBLISHERS, 162, 5-6, 597-602, Mar. 2011, Peer-reviwed, We consider He-4 particles confined in a quasi-one-dimensional nanoscale channel in the range of liquid density, and numerically calculate the energy per particle by the imaginary time path integral Monte Carlo method. When the channel diameter becomes less than 1.6 nm, T (onset), at which the energy drops due to the particle exchange effect, shifts to lower temperature, and disappears below 0.48 nm. The diameter dependence of T (onset) is similar to the behavior of the superfluid onset temperature, T (o), for mesoporous materials FSM16 observed by the torsional oscillator.
Scientific journal, English - Mechanical Response of He-4 Films Adsorbed on Graphite with a Quartz Tuning Fork
F. Nihei; K. Ideura; H. Kobayashi; J. Taniguchi; M. Suzuki
JOURNAL OF LOW TEMPERATURE PHYSICS, SPRINGER/PLENUM PUBLISHERS, 162, 5-6, 559-564, Mar. 2011, Peer-reviwed, We have carried out quartz-crystal microbalance (QCM) experiments of 32 kHz quartz tuning fork for He-4 films adsorbed on Grafoil, and have measured the temperature dependence of the resonance frequency and Q value for various areal densities. It was found that the frequency does not decrease exactly in proportion to the areal density. This means that the film still undergoes decoupling partly, although it is strongly suppressed from that of 5 MHz QCM measurements. Above the three-atom thick film, the decoupling due to the superfluidity of the overlayer is observed. In addition, we found that the competition between the superfluidity and the slippage takes place for a large oscillation amplitude. From the comparison with 5 MHz QCM measurements, it is concluded that the acceleration of substrate plays an important role in the slippage.
Scientific journal, English - 22pPSB-44 Interface friction of Kr films adsorbed on single-crystalline mica substrate
Kobayashi H.; Taniguchi J.; Suzuki M.; Arakawa I.
Meeting Abstracts of the Physical Society of Japan, The Physical Society of Japan, 66, 0, 258-258, 2011, Peer-reviwed
Japanese - Superfluidity of liquid H4 e confined to one-dimensional straight nanochannel structures
Junko Taniguchi; Yosuke Aoki; Masaru Suzuki
Physical Review B - Condensed Matter and Materials Physics, 82, 10, 15 Sep. 2010, Peer-reviwed, Superfluidity of liquid H4 e confined in one-dimensional (1D) nanometer-size channels has been studied by means of a torsional oscillator. When the channel is larger than 2.8 nm in diameter, liquid H4 e becomes superfluid at low temperatures and a dissipation due to quantized vortex is observed. The superfluid onset temperature is 1.8 K at 0.14 MPa for the 4.7 nm channel and 0.89 K at 0.01 MPa for the 2.8 nm channel. For the latter, it is suppressed strongly under the application of pressure, and continuously approaches zero at around 2.1 MPa at absolute zero, which suggests a quantum phase transition between the superfluid and nonsuperfluid states in the 1D channel. © 2010 The American Physical Society.
Scientific journal, English - Superfluidity of liquid He-4 confined to one-dimensional straight nanochannel structures
Junko Taniguchi; Yosuke Aoki; Masaru Suzuki
PHYSICAL REVIEW B, AMER PHYSICAL SOC, 82, 10, 104510-1-5, Sep. 2010, Peer-reviwed, Superfluidity of liquid He-4 confined in one-dimensional (1D) nanometer-size channels has been studied by means of a torsional oscillator. When the channel is larger than 2.8 nm in diameter, liquid 4He becomes superfluid at low temperatures and a dissipation due to quantized vortex is observed. The superfluid onset temperature is 1.8 K at 0.14 MPa for the 4.7 nm channel and 0.89 K at 0.01 MPa for the 2.8 nm channel. For the latter, it is suppressed strongly under the application of pressure, and continuously approaches zero at around 2.1 MPa at absolute zero, which suggests a quantum phase transition between the superfluid and nonsuperfluid states in the 1D channel.
Scientific journal, English - Ultrasound Measurements of He-4 Confined in a Nano-porous Glass
Toshiaki Kobayashi; Junko Taniguchi; Ayanori Saito; Satoshi Fukazawa; Masaru Suzuki; Keiya Shirahama
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, PHYSICAL SOC JAPAN, 79, 8, 084601-1,-6, Aug. 2010, Peer-reviwed, We have carried out ultrasound measurements for He-4 confined in a nano-porous glass, Gelsil. The sound velocity of Gelsil glass in a vacuum is determined by the two-level system (TLS) contribution. Regardless of whether He-4 in the pore is liquid or solid, there exists an additional sound velocity change due to the relaxation of ultrasound stresses by a thermal activation mechanism. It was found that the different heat treatment of Gelsil glass affects both this relaxation and the superfluidity of He-4 in the pore.
Scientific journal, English - Mechanical response of Kr films adsorbed on graphite substrate with a quartz tuning fork
Hajime Kobayashi; Junko Taniguchi; Masaru Suzuki; Kouji Miura; Ichiro Arakawa
INTERNATIONAL CONFERENCE ON SCIENCE OF FRICTION 2010 (ICSF2010), IOP PUBLISHING LTD, 258, 012018-1--6, 2010, Peer-reviwed, We have developed a quartz-crystal microbalance (QCM) using a quartz tuning fork resonator, and have carried out experiments for Kr films adsorbed on a single crystalline graphite at LN2 temperature. For the monolayer film, the coupled mass to the oscillating substrate is significantly small until the film enters the commensurate (C) phase. It starts to increase at the C phase, and the increase in the coupled mass with respect to the coverage decreases at the coexistence phase between the C and the incommensurate (IC) phases. It is enhanced again when the film enters the IC phase. We compared the observed behavior with that of 5 MHz QCM experiments, and found that the sliding motion does not depend on oscillation frequency.
International conference proceedings, English - Development of a combined atomic force microscope with an AT-cut quartz resonator
Daisuke Inoue; Nariko Hosomi; Junko Taniguchi; Masaru Suzuki; Makoto Ishikawa; Kouji Miura
INTERNATIONAL CONFERENCE ON SCIENCE OF FRICTION 2010 (ICSF2010), IOP PUBLISHING LTD, 258, 012019-1-5, 2010, Peer-reviwed, To study the microscopic mechanism of energy dissipation due to sliding motion, we are developing a combined atomic force microscope (AFM) with a quartz crystal microbalance (QCM) resonator. In this system, the loading force is controlled by AFM, while the energy dissipation is measured by the change in Q value of the quartz crystal. At room temperature, we have checked the energy dissipation for several substrates as a function of loading force. The energy dissipation depends both on substrate material and on oscillation amplitude.
International conference proceedings, English - Simultaneous Measurements of an Ultrasound and a Torsional Oscillator for Pressurized He-4 in a Nanoporous Glass
Toshiaki Kobayashi; Ayanori Saito; Junko Taniguchi; Masaru Suzuki; Keiya Shirahama
JOURNAL OF LOW TEMPERATURE PHYSICS, SPRINGER/PLENUM PUBLISHERS, 158, 1-2, 250-255, Jan. 2010, Peer-reviwed, Recently, torsional oscillator (Yamamoto et al. in Phys. Rev. Lett. 93: 075302, 2004) and ultrasound (Kobayashi et al. in AIP Conf. Proc. 128: 797, 2007) measurements were carried out for pressurized He-4 filled in a nanoporous glass (Gelsil), and the superfluid transition temperature T-C shows a different pressure dependence. Thus motivated, we have performed simultaneous measurements with a torsional oscillator and with ultrasound for pressurized He-4 in Gelsil. T-C is in agreement between the two techniques at all pressures, and the superfluid component above 0.5 K shows most of the same temperature dependence. Furthermore, it was found that the chi-factor (the fraction of superfluid which remains locked to the substrate) is independent of measuring frequency between the torsional oscillator (kHz-order) and the ultrasound (MHz-order) ranges.
Scientific journal, English - Sliding Friction of Kr Films Adsorbed on Graphite
Hajime Kobayashi; Junko Taniguchi; Masaru Suzuki; Kouji Miura; Ichiro Arakawa
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, PHYSICAL SOC JAPAN, 79, 1, 014602-1,-6, Jan. 2010, Peer-reviwed, We have carried Out quartz crystal microbalance (QCM) experiments for Kr films adsorbed on exfoliated graphite from a single crystal, and have examined the coverage dependence of the sliding friction and the depinning transition up to the bilayer film. For the monolayer film, the coupled mass density appears at the commensurate and fluid (C+F) phase. An increase of this density starts at the commensurate (C) phase and continues at the incommensurate (IC) phase after the C-IC transition. It was found that the monolayer film slides not uniformly but partly on the substrate, and that the slip time is 60 ns at the C phase. On the other hand, the film around the layer completion slides almost uniformly, and its slip time is about 10 ns. For the bilayer film, the experimental data are reasonably explained by a model in which the slip occurs at the boundary between the first and second atomic layers, in addition to the boundary between the film and the substrate. For the oscillation amplitude sweep at a constant coverage, a rapid change in frequency was observed for the monolayer and bilayer films, which is attributed to the depinning transition. This magnitude takes the minimum value around the layer completion.
Scientific journal, English - Nanocomposite Materials of Alternately Stacked C-60 Monolayer and Graphene
Makoto Ishikawa; Shu Kamiya; Shoji Yoshimoto; Masaru Suzuki; Daisuke Kuwahara; Naruo Sasaki; Kouji Miura
JOURNAL OF NANOMATERIALS, HINDAWI PUBLISHING CORPORATION, 2010, 891514-1,-6, 2010, Peer-reviwed, We synthesized the novel nanocomposite consisting alternately of a stacked single graphene sheet and a C-60 monolayer by using the graphite intercalation technique in which alkylamine molecules help intercalate large C-60 molecules into the graphite. Moreover, it is found that the intercalated C-60 molecules can rotate in between single graphene sheets by using C-13 NMR measurements. This preparation method provides a general way for intercalating huge fullerene molecules into graphite, which will lead to promising materials with novel mechanical, physical, and electrical properties.
Scientific journal, English - Rotational Motion of C_60 in C60 Intercalated Graphite Films
N. Hosomi; M. Suzuki; D. Kuwahara; M. Ishikawa; M. Kato; K. Miura
Proceedings of World Tribology Congress 2009, 252, Sep. 2009, Peer-reviwed
International conference proceedings, English - Competition between the Slippage and the Superfluidity of 4He Films
H. Kobayashi; N. Hosomi; J. Taniguchi; Masaru Suzuki; T. Minoguchi
Proceedings of World Tribology Congress 2009, 270, Sep. 2009, Peer-reviwed
International conference proceedings, English - Sliding Friction of Multilayer Helium Films
Masaru Suzuki
Proceedings of World Tribology Congress 2009, 852, Sep. 2009, Peer-reviwed
International conference proceedings, English - Dynamical sticking of a solid He-4 film with superfluid overlayer
Nariko Hosomi; Junko Taniguchi; Masaru Suzuki; Tomoki Minoguchi
PHYSICAL REVIEW B, AMER PHYSICAL SOC, 79, 17, 172503-1,-4, May 2009, Peer-reviwed, We observed a phenomenon in a quartz-crystal microbalance experiment for solid He-4 films with liquid overlayer on graphite. The solid atomic layers underneath the superfluid layer stop slipping from the oscillating substrate when the superfluid density grows up to a certain magnitude. This phenomenon can be explained by a mechanism in which the mass transport caused by the motion of edge dislocations in solid atomic layers is canceled by counterflow of the superfluid overlayer.
Scientific journal, English - Size Dependence of Superfluidity for He-4 Confined in FSM16
Junko Taniguchi; Rina Fujii; Masaru Suzuki
25TH INTERNATIONAL CONFERENCE ON LOW TEMPERATURE PHYSICS (LT25), PART 3, IOP PUBLISHING LTD, 150, 032108-1,-4, 2009, Peer-reviwed, The superfluidity for liquid He-4 confined in one-dimensional channels has been studied by means of torsional oscillator. In the present experiments, FSM16 with the channel of 4.7-nm in diameter was used, together with preplating monolayer N-2 film on the channel ( the effective diameter of 4.1 nm). As the channel is preplated, the superfluid transition temperature at 0.1 MPa shifts to a lower temperature from 1.81 K for 4.7-nm channel to 1.69 K for N-2 preplated one. The results show that the superfluidity is suppressed strongly with decreasing diameter.
International conference proceedings, English - Sliding Friction of Kr Films Adsorbed on Single-Crystalline Graphite Substrate
Hajime Kobayashi; Jyunko Taniguchi; Masaru Suzuki; Kouji Miura; Ichiro Arakawa
25TH INTERNATIONAL CONFERENCE ON LOW TEMPERATURE PHYSICS (LT25), PART 3, IOP PUBLISHING LTD, 150, 032045-1,-4, 2009, Peer-reviwed, We have performed a quartz crystal microbalance (QCM) experiment for Kr films adsorbed on a single-crystalline graphite substrate at various temperatures. The substrate enables us to study the oscillation direction dependence of the sliding friction. In the present experiment, the direction is parallel to the a-axis of graphite. It was found that the resonance frequency at 85 K does not change greatly until the film enters the commensurate phase. At the commensurate phase, the resonance frequency starts to decrease. In addition, at the transition from the commensurate phase to the incommensurate phase, the coverage dependence of frequency changes slightly.
International conference proceedings, English - Competition between the Superfluidity and the Slippage of He-4 Films Adsorbed on Porous Gold
K. Ideura; H. Kobayashi; N. Hosomi; J. Taniguchi; M. Suzuki
25TH INTERNATIONAL CONFERENCE ON LOW TEMPERATURE PHYSICS (LT25), PART 3, IOP PUBLISHING LTD, 150, 032032-1,-4, 2009, Peer-reviwed, We have carried out QCM measurements for He-4 films adsorbed on porous gold in the crossover region between the superfluidity and the slippage. In relative low areal densities, the resonance frequency increases gradually below T-S due to the slippage of solid film, while the superfluid onset is observed in high areal densities. In the crossover region, we observed a peculiar behavior: The increase in the resonance frequency below T-S is suddenly suppressed at a certain temperature T-D. From these observations, it is concluded that the superfluidity and the slippage of He-4 competes with each other.
International conference proceedings, English - Effect of He-3 on Superfluid He-4 Films Adsorbed on Grafoil
Nariko Hosomi; Junko Taniguchi; Masaru Suzuki; Tomoki Minoguchi
25TH INTERNATIONAL CONFERENCE ON LOW TEMPERATURE PHYSICS (LT25), PART 3, IOP PUBLISHING LTD, 150, 032031-1,-4, 2009, Peer-reviwed, We have studied an effect of He-3 on superfluid He-4 films adsorbed on exfoliated graphite (Grafoil) using a quartz-crystal microbalance (QCM) technique. It is known that zero-temperature superfluid mass and superfluid onset temperature of He-4 films adsorbed on porous gold substrate are suppressed, or even eliminated with the addition of He-3. We found that the superfluid onset temperature of He-4 films on graphite decreases with the addition of He-3. However, the superfluid mass does not increase monotonically with decreasing temperature; it has a peak and is suppressed below a certain temperature, which suggests a phase separation of the film at low temperatures.
International conference proceedings, English - Significant softening of c(66) and hidden order parameter in the magnetic ordered state of La2-xCaxCoO4 (0.4 <= x <= 0.7)
K. Horigane; T. Kobayashi; M. Suzuki; K. Abe; K. Asai; J. Akimitsu
PHYSICAL REVIEW B, AMER PHYSICAL SOC, 78, 14, 144108-1,-6, Oct. 2008, Peer-reviwed, We have measured the longitudinal and transverse sound velocities of La2-xCaxCoO4 (0.4 <= x <= 0.7) propagating along [100], [110], and [001] from 200 K down to 3 K with a frequency of 10 MHz. It was found that c(66) shows a remarkable softening below Co2+ spin-ordering temperature T-N in the whole doping range, while c(11)-c(12)/2 exhibits a clear hardening below Co3+ spin-ordering temperature T-N2 only when x=0.5. To explain the observed anomaly, the Landau free energy for the La2-xCaxCoO4 system has been constructed, including the coupling energy between elastic strains and a two-dimensional order parameter (Q(1),Q(2)), having a spatial modulation along [110] or [<overline>1</overline>10]. We argued that this represents orbital order, and it is this order that leads to the softening of c(66).
Scientific journal, English - High-field magnetostriction of the spin-state transition compound LaCoO3
Keisuke Sato; Mikhail I. Bartashevich; Tsuneaki Goto; Yoshihiko Kobayashi; Masaru Suzuki; Kichizo Asai; Akira Matsuo; Koichi Kindo
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, PHYSICAL SOC JAPAN, 77, 2, 024601-1,-6, Feb. 2008, Peer-reviwed, The transverse and longitudinal magnetostrictions of LaCoO3 have been measured in pulsed magnetic fields of up to 35 T in the temperature range between 4.2 and 300 K. The magnetostrictions are proportional to the squared magnetic field of up to B-0 = 25 T. The magnetostrictions at B < B-0 are analyzed with a spin-state transition model involving a nonmagnetic ground state and a magnetic excited state for Co ions where Co ions in the latter have a larger optimum lattice volume than those in the former. The observed magnetostrictions are well interpreted by the excited state with g = 3.35 and the excitation energy of A = 140 K, which are consistent with those obtained in an electron spin resonance study [Noguchi et al.: Phys. Rev. B 66 (2002) 0944041 but do not reproduce the observed magnetization. The analysis based on the model and a comparison of the present data to the pressure dependence of the magnetization suggest that the elastic energy represented in terms of only the lattice volume is insufficient for the quantitative description of magnetoelastic phenomena in LaCoO3. A sharp increase in the longitudinal magnetostriction with a large hysteresis observed in B > B-0 and T > 60 K is ascribed to a change in the domain structure of the twinned LaCoO3 crystal induced by a magnetic field.
Scientific journal, English - Torsional oscillator measurements of liquid He-4 confined in 2.2-nm channels of FSM
J. Taniguchi; M. Suzuki
JOURNAL OF LOW TEMPERATURE PHYSICS, SPRINGER/PLENUM PUBLISHERS, 150, 3-4, 347-352, Feb. 2008, Peer-reviwed, We have performed torsional oscillator measurements for liquid He-4 confined in 2.2-nm channels of FSM up to 2.45 MPa. At 0.1 MPa, the resonant frequency increases with decreasing temperature. It shows a small bend at about 0.9 K, and then keeps increasing down to the lowest temperature, 0.16 K. The magnitude of the frequency increase below 0.9 K is suppressed with increasing pressure, while the temperature of the bend shows almost no pressure dependence.
Scientific journal, English - Sliding friction of multilayer He-4 films adsorbed on graphite
Nariko Hosomi; Masaru Suzuki
PHYSICAL REVIEW B, AMER PHYSICAL SOC, 77, 2, 024501-1,-8, Jan. 2008, Peer-reviwed, We have carried out a quartz crystal microbalance experiment for multilayer He-4 films adsorbed on graphite. We analyzed changes in the resonance frequency and Q value using the multilayer model, and obtained the sliding friction of the boundary between the atomic layers in the film, in addition to the boundary between the film and the substrate. The sliding friction of the boundary of the first and second atomic layers is much smaller than that of the boundary between the film and the substrate.
Scientific journal, English - Comparison between torsional oscillator and ultrasonic measurements of He-4 confined in nano-porous media
J. Taniguchi; H. Ichida; Y. Aoki; S. Fukazawa; M. Hieda; M. Suzuki
JOURNAL OF LOW TEMPERATURE PHYSICS, SPRINGER/PLENUM PUBLISHERS, 148, 5-6, 791-795, Sep. 2007, Peer-reviwed, We have performed torsional oscillator and ultrasonic measurements for He-4 confined in 2D nano-porous substrate, hectorite. For He-4 films, the resonance frequency of the torsional oscillator increases rapidly just below a superfluid transition temperature (T (C) ), and then becomes constant at the lower temperature. In contrast, the sound velocity below T (C) increases monotonically with decreasing temperature. For liquid He-4 the sound velocity has a small bend at T (b) of about 0.9 K. Its increase below T (b) is enhanced as the pressure is increased.
Scientific journal, English - Interfacial friction of He-3 films adsorbed on grafoil
Nariko Hosomi; Masaru Suzuki
JOURNAL OF LOW TEMPERATURE PHYSICS, SPRINGER/PLENUM PUBLISHERS, 148, 5-6, 773-777, Sep. 2007, Peer-reviwed, We measured the interfacial friction of He-3 films adsorbed on Grafoil (exfoliated graphite) using the quartz-crystal microbalance (QCM) technique, and compare present results with those of He-4 films. In the same manner as He-4 films, the friction decreases below a certain temperature T-S , and T-S depends on the areal density of He-3 film. In two-atom and three-atom thick films, however, T-S of He-3 films is lower than that of He-4 films. Furthermore, the decrease in the friction still remains above five-atom thick films of He-3 while it disappears in four-atom thick films of He-4 and the superfluid onset is manifest.
Scientific journal, English - Sliding friction of helium films in the metastable state and its relaxation
Nariko Hosomi; Ayano Tanabe; Masaru Suzuki; Mitsunori Hieda
PHYSICAL REVIEW B, AMER PHYSICAL SOC, 75, 6, 064513-1,5, Feb. 2007, Peer-reviwed, We measured the sliding friction of (4)He films adsorbed on Grafoil using the quartz-crystal microbalance technique. In the low-temperature regime, this friction remains metastable after switching off the oscillation amplitude before relaxing to the value determined by the amplitude. The relaxation of this friction is qualitatively different for decreasing and increasing amplitudes. In the former case, the relaxation depends strongly on temperature and has a quasiexponential time dependence, while it has a quasilogarithmic one in the latter case. We can explain both cases of relaxation by a model of a small low-friction domain, which is created or annihilated by overcoming a potential barrier.
Scientific journal, English - Physical properties of C-60 intercalated graphite films
T. Nakahara; N. Hosomi; J. Taniguchi; M. Suzuki; T. Sato; K. Abe; D. Kuwahara; M. Ishikawa; M. Kato; K. Miura
INTERNATIONAL CONFERENCE ON SCIENCE OF FRICTION, IOP PUBLISHING LTD, 89, 012002, 2007, Peer-reviwed, Recently, Miura and Tsuda have synthesized C-60 intercalated graphite film (C-60/Gr) and reported that the C-60/Gr consists of alternating close-packed C-60 monolayers and graphite layers. They also found that its frictional force is minimal up to the loading force of 100 nN using AFM. [Miura K and Tsuda D 2005 e-J. Surf. Sci. Nanotech. 3 21] Thus, we have started to study the physical properties of C-60/Gr and carried out NMR, Raman scattering and specific heat measurements. These results suggest that C-60 in C-60/Gr rotates at room temperature.
International conference proceedings, English - Sliding friction of Kr films adsorbed on graphite substrate
H. Kobayashi; J. Taniguchi; M. Suzuki; K. Miura; I. Arakawa
INTERNATIONAL CONFERENCE ON SCIENCE OF FRICTION, IOP PUBLISHING LTD, 89, 012006, 2007, Peer-reviwed, We have carried out a quartz crystal microbalance experiment of Kr films adsorbed on exfoliated single crystalline graphite. The graphite enables us to study the direction dependence of the sliding friction because it remains the crystal orientation after exfoliating. In the present experiment, the oscillation of the crystal is inclined at about 300 to the a-axis of graphite. It was found that the resonance frequency does not decrease until the commensurate phase and decreases rapidly at this phase.
International conference proceedings, English - Sliding friction of Kr films adsorbed on graphite substrate
H. Kobayashi; J. Taniguchi; M. Suzuki; K. Miura; I. Arakawa
INTERNATIONAL CONFERENCE ON SCIENCE OF FRICTION, IOP PUBLISHING LTD, 89, 266, 2007, Peer-reviwed, We have carried out a quartz crystal microbalance experiment of Kr films adsorbed on exfoliated single crystalline graphite. The graphite enables us to study the direction dependence of the sliding friction because it remains the crystal orientation after exfoliating. In the present experiment, the oscillation of the crystal is inclined at about 300 to the a-axis of graphite. It was found that the resonance frequency does not decrease until the commensurate phase and decreases rapidly at this phase.
International conference proceedings, English - Search of superfluidity of solid He-4 in a porous vycor glass by means of the ultrasound technique
T. Kobayashi; S. Fukazawa; J. Taniguchi; M. Suzuki; K. Shirahama
LOW TEMPERATURE PHYSICS, PTS A AND B, AMER INST PHYSICS, 850, 333-+, 2006, Peer-reviwed, Kim and Chan have reported that solid He-4 shows a reduction of the rotational moment of inertia below 0.2 K, which suggests an onset of superfluidity. Ultrasound should be sensitive to mass decoupling caused by superfluidity. If a superfluid component exists, the sound velocity of a porous material filled with solid 4He could increase. We have carried out ultrasonic measurements for a porous Vycor glass filled with solid 4He. Since the reported "critical velocity" is very low, we have adopted a continuous wave resonance technique which realizes the oscillating velocity less than 1 X 10(-7) m/s. The resolution of the sound velocity is 10(-5) for small oscillating velocities, and is enough to detect the expected mass decoupling. Although the present experimental conditions are rather limited, no signature of supersolid has been observed.
International conference proceedings, English - Interfacial friction of He-4 films adsorbed on grafoil preplated with Kr
N. Hosomi; S. Takizawa; A. Tanabe; Y. Aoki; J. Taniguchi; M. Hieda; M. Suzuki
LOW TEMPERATURE PHYSICS, PTS A AND B, AMER INST PHYSICS, 850, 271-+, 2006, Peer-reviwed, We report results for interfacial friction of nonsuperfluid He-4 films adsorbed on Grafoil (exfoliated graphite) preplated with one atomic layer of Kr (He-4/Kr/Gr). In the present experiment, the quartz-crystal microbalance (QCM) technique was adopted, and the friction was measured down to 0.5 K for several oscillating amplitudes, ranging from 0.1 to 1 nm at 5 MHz. Above about the first layer completion, a decrease in the friction was clearly observed for a large amplitude below a certain temerature T-S. This decrease occurs abruptly at around the second layer completion. Although He-4/Kr/Gr has a lower T-S than He-4 adsorbed on bare Grafoil when He-4 is two atoms thick, the areal density dependence of T(S)is similar for the two systems.
International conference proceedings, English - Interfacial friction of He-4 films adsorbed on porous gold
J. Taniguchi; K. Wataru; K. Hasegawa; M. Hieda; M. Suzuki
LOW TEMPERATURE PHYSICS, PTS A AND B, AMER INST PHYSICS, 850, 279-+, 2006, Peer-reviwed, We measured the interfacial friction of nonsuperfluid He-4 films adsorbed on porous gold using the quartz-crystal microbalance (QCM) technique. Above about the first layer completion, decoupling due to a decrease in the interfacial ftiction was observed for a large oscillation amplitude of 1.6 nm below a certain temperature T-S, which depends on the areal density of He-4. The completion of the first layer and the inert layer was found to strongly affect the interfacial friction.
International conference proceedings, English - Slippage of nonsuperfluid 4He films adsorbed on Grafoil
Masaru Suzuki; Nariko Hosomi; Ayano Tanabe; Mitsunori Hieda
Journal of Physics and Chemistry of Solids, 66, 8-9, 1527-1531, Aug. 2005, Peer-reviwed, We measured the decoupling of 4He films adsorbed on Grafoil using the quartz crystal microbalance (QCM) technique. It was found that nonsuperfluid 4He films decouple from the oscillating substrate, and that the degree of decoupling depends on the oscillating amplitude and the temperature. The amplitude dependence of the decoupling demonstrates clearly that the frictional force between Grafoil substrate and 4He film is not proportional to the sliding velocity. On the other hand, the temperature dependence of the decoupling shows that this force decreases below a certain temperature, i.e., the film sets in a low-friction state at low temperatures. In addition, it was found that this state remains metastable concerning the change in the oscillating amplitude. © 2005 Elsevier Ltd. All rights reserved.
International conference proceedings, English - Slippage of He-4 films adsorbed on porous gold
K Wataru; J Taniguchi; M Hieda; M Suzuki
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS, PERGAMON-ELSEVIER SCIENCE LTD, 66, 8-9, 1535-1538, Aug. 2005, We measured the slippage of nonsuperfluid He-4 films adsorbed on a porous gold substrate using the quartz-crystal microbalance (QCM) technique. The substrate has a highly uniform porous structure, and its effective surface area was 20 times larger than that of a flat substrate. It was found that the degree of slippage between He-4 films and the substrate increases below a certain temperature T-S, and that T-S decreases with increasing He-4 areal density. This increase depends strongly on the oscillating amplitude of the quartz crystal. (c) 2005 Elsevier Ltd. All rights reserved.
Scientific journal, English - Slippage of nonsuperfluid He-4 films adsorbed on Grafoil
M Suzuki; N Hosomi; A Tanabe; M Hieda
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS, PERGAMON-ELSEVIER SCIENCE LTD, 66, 8-9, 1527-1531, Aug. 2005, Peer-reviwed, We measured the decoupling of He-4 films adsorbed on Grafoil using the quartz crystal microbalance (QCM) technique. It was found that nonsuperfluid He-4 films decouple from the oscillating substrate, and that the degree of decoupling depends on the oscillating amplitude and the temperature. The amplitude dependence of the decoupling demonstrates clearly that the frictional force between Grafoil substrate and He-4 film is not proportional to the sliding velocity. On the other hand, the temperature dependence of the decoupling shows that this force decreases below a certain temperature, i.e., the film sets in a low-friction state at low temperatures. In addition, it was found that this state remains metastable concerning the change in the oscillating amplitude. (c) 2005 Elsevier Ltd. All rights reserved.
Scientific journal, English - Mn-55 NMR in ferromagnetic perovskites RENi0.5Mn0.5O3 (RE = rare earth element)
K Asai; N Kobayashi; T Bairo; N Kaneko; Y Kobayashi; M Suzuki; Y Satoh; M Mizoguchi
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, PHYSICAL SOC JAPAN, 74, 4, 1289-1296, Apr. 2005, Peer-reviwed, The hyperfine magnetic fields, H-HF, at Mn-55 were measured by NMR at 2 K for ferromagnetically ordered double perovskites REMn0.5Ni0.5O3 (RE = rare earth element). The field HHF tends to decrease as RE goes from La (-258 kOe) to Lu (-282 kOe). In addition to the overall RE dependence a break is found between RE = Tb and Dy. The field H-HF is interpreted as the sum of H-HF,H-Mn4+ arising from the unpaired electrons in Mn4+ to which Mn-55 belongs and H-STHF supertransferred from the neighboring Ni2+ ions. The present result shows that H-STHF decreases by 30-55%, as RE goes from La to Lu, due to the reduction of the covalency of Ni2+-O2- and Mn4+-O2- bonds, in addition to a 25% decrease arising from the cos(2) theta-type bond angle dependence of H-STHF. The reduction of the covalency as RE goes from La to heavier elements reasonably explains the non-linear cos(2) theta dependence of T-C of the present oxides. The magnetic moments of RE ions do not contribute to the "average" H-HF. but give rise to large transverse relaxation rates by their fluctuation, which is suppressed by an applied magnetic field.
Scientific journal, English - Low-friction State of 4He Films Adsorbed on Grafoil
N. Hosomi; A. Tanabe; M. Hieda; M. Suzuki
J. Phys. Chem. Solids, 66, 1527-1531, 2005, Peer-reviwed
Scientific journal, English - Slippage of He-4 films adsorbed on grafoil
N Hosomi; M Suzuki; M Hieda
JOURNAL OF LOW TEMPERATURE PHYSICS, KLUWER ACADEMIC/PLENUM PUBL, 134, 1-2, 37-42, Jan. 2004, Peer-reviwed, We applied the quartz-crystal microbalance (QCM) technique to He-4 films adsorbed on grafoil. It was found that both of nonsuperfluid He-4 films and the inert layers underneath the superfluid film slip under a certain condition at low temperatures, and that the temperature at which these films start to slip depends on the 4He areal density. In addition, this slippage also depended strongly on the amplitude of the quartz crystal.
Scientific journal, English - Ultrasonic study on superconducting HoNi2B2C and Ho0.75Y0.25Ni2B2C
M Suetake; Y Takahashi; M Suzuki; K Abe; K Asai; K Kuroki; S Isida; H Takeya
PHYSICA B-CONDENSED MATTER, ELSEVIER SCIENCE BV, 329, 539-540, May 2003, Peer-reviwed, We performed ultrasonic measurements for HoNi2B2C and Ho0.75Y0.25Ni2B2C single crystals between 1.7 and 80 K under various magnetic field. In zero field, C-66 for HoNi2B2C decreases continuously on lowering temperature in a wide temperature region below 80 K, and showed a discontinuous softening and recovering at 5.5 and 3.8 K, respectively. In contrast, (C-11-C-12)/2 remained almost constant in the whole temperature region. In the field applied along the b(a)-axis, the softening Of C-66 was largely suppressed, which suggests that the softening is magnetic in origin. A similar softening Of C-66 was also observed for Ho0.75Y0.25Ni2B2C. (C) 2003 Elsevier Science B.V. All rights reserved.
Scientific journal, English - Interfacial tension of He-3-He-4 mixture in the low temperature region
K Ohishi; M Suzuki; A Sato
PHYSICA B-CONDENSED MATTER, ELSEVIER SCIENCE BV, 329, 174-175, May 2003, Peer-reviwed, We measured the interfacial tension of He-3-He-4 mixture by means of the capillary-rise method. Change in the capillary-rise was obtained from the capacitance change of two capacitors with different gap widths. It was found that the present data are in good agreement with those obtained from the resonance of the interfacial wave, and that the temperature dependence of this tension varies as T-2 down to 100 mK. (C) 2003 Elsevier Science B.V. All rights reserved.
Scientific journal, English - Slippage of nonsuperfluid helium films
M Suzuki; M Hieda
PHYSICA B-CONDENSED MATTER, ELSEVIER SCIENCE BV, 329, 246-247, May 2003, Peer-reviwed, We measured the slippage of nonsuperfluid He-4 films adsorbed on two kinds of substrates, grafoil and hectorite, and found that a large part of these films undergo slipping at low temperatures. Furthermore, it was found that the He-4 areal density dependence of the slippage is rather different between these substrates. In hectorite, the slippage is inhibited as the fluid state appears at absolute zero. On the other hand, in grafoil, this state does not suppress the slippage, a It least, as the He-4 areal density is low. This may be attributed to the difference in the structure of these films. (C) 2003 Elsevier Science B.V. All rights reserved.
Scientific journal, English - QCM studies of He-4 films adsorbed on grafoil
T Ogura; N Hosomi; M Hieda; M Suzuki
PHYSICA B-CONDENSED MATTER, ELSEVIER SCIENCE BV, 329, 256-257, May 2003, Peer-reviwed, We applied the quartz-crystal microbalance technique to a graphite substrate, and measured the slippage of nonsuperfluid He-4 films at MHz-frequency range, as well as the superfluidity. It was found that nonsuperfluid He-4 films undergo slipping at low temperatures, and that this slippage depends strongly on He-4 areal density. (C) 2003 Elsevier Science B.V. All rights reserved.
Scientific journal, English - High-resolution coherent Raman spectroscopy of vibrons in solid parahydrogen
K Kuroda; A Koreeda; S Takayanagi; M Suzuki; K Hakuta
PHYSICAL REVIEW B, AMERICAN PHYSICAL SOC, 67, 18, 184303~1-5, May 2003, Peer-reviwed, Coherent Raman spectroscopy is carried out for the Q(1)(0) vibron of solid parahydrogen crystal with a spectral resolution better than 1 MHz. The Raman spectrum is measured for the temperature from 4.2 to 13 K under constant molecular density condition. We show that the temperature dependence of the Raman spectrum should be quantitatively described via the interaction between vibrons and thermal acoustic phonons through a two-phonon scattering process. We also investigate the effect of molecular density on the Raman shift and obtain the hopping interaction strength for the vibron band.
Scientific journal, English - Temperature Dependence of the Raman Shift and Raman Width of Solid Parahydrogen: Effect of Vibron-Phonon Scattering
F. Le Kien; A. Koreeda; K. Kuroda; M. Suzuki; K. Hakuta
Jpn. J. Appl. Phys., 42, 3483-3489, 2003, Peer-reviwed
Scientific journal, English - Slippage of nonsuperfluid He-4 films on Ag
T Koike; M Hieda; M Suzuki
JOURNAL OF LOW TEMPERATURE PHYSICS, KLUWER ACADEMIC/PLENUM PUBL, 126, 1-2, 391-396, Jan. 2002, Peer-reviwed, We measured the mechanical response of nonsuperfhiid He-4 films adsorbed on a Ag substrate using the quartz-crystal microbalance technique. In He-4 coverages from 0.06 to 0.1 atoms/Angstrom(2), we observed that the resonance frequency increases at low temperatures accompanied by a decrease in Q-value. This behavior suggests that nonsuperfluid He-4 films undergo partial slipping relative to the Ag substrate.
Scientific journal, English - Impurity effects on the slippage of nonsuperfiuid helium films
T Nishino; T Watanabe; M Hieda; M Suzuki; N Wada; K Torii
JOURNAL OF LOW TEMPERATURE PHYSICS, SPRINGER/PLENUM PUBLISHERS, 126, 1-2, 397-402, Jan. 2002, Peer-reviwed, Me measured the mechanical response of (4)He films adsorbed on an oscillating substrate with a small amount of N(2) molecules using an ultrasonic technique. Compared with the substrate with no N(2) molecules, it was found that nonsuperfluid (4)He films undergo slipping at lower temperature. This means that the frictional force acting on these films is increased by N(2) molecules adsorbed on the substrate.
Scientific journal, English - Coherent Brillouin spectroscopy in solid parahydrogen
K Kuroda; JZ Li; M Suzuki; M Katsuragawa; K Hakuta
JOURNAL OF LOW TEMPERATURE PHYSICS, KLUWER ACADEMIC/PLENUM PUBL, 125, 1-2, 39-48, Oct. 2001, Peer-reviwed, We applied coherent Brillouin spectroscopy to solid parahydrogen, and measured the Brillouin spectra of longitudinal acoustic modes at 5.6 K. It was found that the linewidth of these spectra is similar to 1.5 MHz. From the observed Brillouin shift and the crystal orientation, the elastic stiffness was determined as C-11 =0.355 +/-0.016 GPa and C-33 =0.432 +/-0.022 GPa.
Scientific journal, English - Surface tension maximum of liquid He-3 - Experimental study
K Matsumoto; Y Okuda; M Suzuki; S Misawa
JOURNAL OF LOW TEMPERATURE PHYSICS, KLUWER ACADEMIC/PLENUM PUBL, 125, 1-2, 59-67, Oct. 2001, Peer-reviwed, The surface tension of liquid He-3 was measured as a function of temperature by means of the capillary rise method. Suzuki et al. [Europhysics Lett. 5, 333 (1988)] reported that the surface tension was almost temperature independent below 120 mK. Here ive have examined it with greater precision and found that it has a small maximum around 100 mK. The surface tension increased with temperature from 35 mK and had a maximum of about 3 x 10(-4) as a fraction of the surface tension at 0 K. It was found that the surface tension maximum can be attributed mainly to the T-4 In T variation which has been theoretically derived by Misawa on the basis of a local approximation for the entropy including Fermi liquid effect.
Scientific journal, English - Measurement of the energy decay rate for the first vibrational-excited-state in solid parahydrogen
JZ Li; M Suzuki; M Katsuragawa; K Hakuta
JOURNAL OF CHEMICAL PHYSICS, AMER INST PHYSICS, 115, 2, 930-932, Jul. 2001, Peer-reviwed, Energy decay rate of the first vibrational excited state for solid parahydrogen is measured from 4.8 K to 12 K. Measurements are carried out using the transient optothermal lensing spectroscopy with the vibrational excitations via the stimulated Raman scattering. The decay rate is measured to be 2.3x10(4) s(-1) at 4.8 K, and it increases to 6.1x10(4) s(-1) by raising the temperature to 12 K. (C) 2001 American Institute of Physics.
Scientific journal, English - Ultrasonic study on superconducting YNi2B2C
S Isida; A Matsushita; H Takeya; M Suzuki
PHYSICA C, ELSEVIER SCIENCE BV, 349, 1-2, 150-154, Jan. 2001, Peer-reviwed, We have measured the elastic constants of YNi2B2C single crystals with T-c = 14.2 K down to 4.2 K. In the normal state, C-44 showed a softening below 65 K, and its magnitude defined as [C-44((65) K)-C-44(T-c)]/C-44(T-c) was approximately 6x10(-4). On the other hand, in the superconducting state, C-44 showed a hardening. This behavior was related to the softening of the acoustic Delta (4) mode, which is observed using inelastic neutron-scattering measurements. In addition, we discuss the pressure dependence of T-c of this material from the change in the slope of the elastic constants at T-c. (C) 2001 Elsevier Science B.V. All rights reserved.
Scientific journal, English - Mechanical response properties of He bilayer films on an oscillating hectorite
M Hieda; T Nishino; M Suzuki; N Wada; K Torii
JOURNAL OF LOW TEMPERATURE PHYSICS, KLUWER ACADEMIC/PLENUM PUBL, 121, 5-6, 507-512, Dec. 2000, Peer-reviwed, We measured the mechanical response of He-3 and He-4 bilayer films on a 2D mesoporous Hectorite from 0.1 K to 4 K using 10MHz ultrasound. Below a certain coverage, we observed the slippage of nonsuperfluid films at low temperatures. This behavior was well described by a film-substrate fractional force with a thermally activated process. Furthermore we found that this slippage is inhibited by the appearance of the fluid slate on the "inert" layer.
Scientific journal, English - Slippage of nonsuperfluid helium films
M Hieda; T Nishino; M Suzuki; N Wada; K Torii
PHYSICAL REVIEW LETTERS, AMER PHYSICAL SOC, 85, 24, 5142-5145, Dec. 2000, Peer-reviwed, We measured the mechanical response of He-3 and He-4 films on an oscillating substrate using an ultrasonic technique. Up to the coverage at which the fluid state appears at absolute zero, a part of the nonsuperfluid He-3 and He-4 films underwent slipping relative to the substrate at low temperatures. From the temperature dependence of the slippage, it was found that a thermally activated process plays an important role in the frictional force of this system.
Scientific journal, English - Interfacial slippage of helium films on 2D mesoporous hectorite
M Hieda; M Suzuki; H Yano; N Wada; K Torii
PHYSICA B, ELSEVIER SCIENCE BV, 284, 125-126, Jul. 2000, Peer-reviwed, We measured by 10 MHz ultrasound the interfacial slippage of He-3 and He-4 films on a vibrating substrate of a two-dimensional mesoporous hectorite. It was found that the interfacial slippage shows a qualitative difference between the monolayer and bilayer films, irrespective of the adsorbate. The monolayer films slipped and underwent decoupling from this substrate at low temperatures. In the bilayer films, in contrast, the first layer of the films was locked on the substrate by the second layer promotion. (C) 2000 Elsevier Science B.V. All rights reserved.
Scientific journal, English - Surface tension maximum of liquid He-3
K Matsumoto; S Hasegawa; M Suzuki; Y Okuda
PHYSICA B, ELSEVIER SCIENCE BV, 284, 198-199, Jul. 2000, Peer-reviwed, The surface tension of liquid He-3 was measured using the capillary-rise method. Suzuki et al. have reported that its temperature dependence was almost quenched below 120 mK. Here we have examined it with higher precision and found that it has a small maximum around 100 mK. The amount of the maximum is about 3 x 10(-4) as a fraction of the surface tension at 0 K. The density of liquid He-3 increases with temperature by about 5 x 10(-4) in Delta rho/rho between 0 and 100 mK. This density change could be one of the reasons of the surface tension maximum around 100 mK. (C) 2000 Elsevier Science B.V. All rights reserved.
Scientific journal, English - Stimulated Raman scattering in liquid hydrogen droplet
S. Uetake; M. Katsuragawa; M. Suzuki; K. Hakuta
Phys. Rev. A, 61, 011803-011806, 2000, Peer-reviwed
Scientific journal, English - Interfacial friction of helium films physisorbed on two-dimensional mesoporous hectorite
M Hieda; T Nishino; M Suzuki; N Wada; K Torii
TRIBOLOGY LETTERS, SPRINGER/PLENUM PUBLISHERS, 9, 3-4, 133-136, 2000, Peer-reviwed, We report the slippage of (4)He films physisorbed on a substrate of a two-dimensional mesoporous hectorite. Up to a certain coverage, a part of nonsuperfluid (4)He films slipped from the oscillating substrate at low temperatures. From the temperature dependence of this slippage, it was found that the thermally activated process plays an important role in the frictional force of this system.
Scientific journal, English - Stimulated Raman scattering in a liquid-hydrogen droplet
S Uetake; M Katsuragawa; M Suzuki; K Hakuta
PHYSICAL REVIEW A, AMERICAN PHYSICAL SOC, 61, 1, art. no.-011803, Jan. 2000, Peer-reviwed, Stimulated Raman scattering (SRS) is investigated in a liquid parahydrogen droplet. We show that the liquid hydrogen droplet readily leads to a high-cavity Q value exceeding 10(9) for whispering gallery modes, and that the SRS in the liquid-hydrogen droplet proceeds not only for vibrational transition but also for rotational transition as in the gas-phase H-2 system, leading to multiorder SRS sidebands covering the whole visible spectral range.
Scientific journal, English - Nonlinear Optical Processes in Solid Hydrogen: New Perspectives on Quantum Optics
K. Hakuta; M. Katsuragawa; M. Suzuki
3rd International Conference on Low Temperature Chemistry, Nagoya, Japan, July 26-30(1999) Invited Paper., 71-72, Jul. 1999
English - Nonlinear Optical Processes in Solid Hydrogen: New Perspectives on Quantum Optics
K. Hakuta; M. Katsuragawa; M. Suzuki
3rd International Conference on Low Temperature Chemistry, Nagoya, Japan, July 26-30(1999)., 71-72, Jul. 1999
English - Stimulated Raman Scattering in Solid Hydrogen based on Adiabatic Preparation of Anti-Phased State
M. Katsuragawa; J. Q. Liang; J.Z. Li; M. Suzuki; K. Hakuta
CLEO/QELS '99, Technical Digest, QthE2, Baltimore, USA, May 23-28 (1999), 195-196, May 1999
English - Mechanical responses of helium films adsorbed on two-dimensional mesoporous hectorite
M Hieda; M Suzuki; K Torii; H Yano; N Wada
PHYSICA B-CONDENSED MATTER, ELSEVIER SCIENCE BV, 263, 370-372, Mar. 1999, The mechanical responses of physisorbed films to the vibration of a substrate were investigated by measuring the sound velocity and attenuation of a two-dimensional mesoporous hectorite. The sound velocity of a hectorite pellet adsorbed by both He-4 and He-3 submonolayer films increased drastically at low temperatures accompanied by the attenuation. The most plausible explanation for this behavior is that helium films decouple from the vibrating substrate at low temperatures. (C) 1999 Elsevier Science B.V. All rights reserved.
Scientific journal, English - Elastic anomalies with the spin-state transitions in LaCoO3
S Murata; S Isida; M Suzuki; Y Kobayashi; K Asai; K Kohn
PHYSICA B, ELSEVIER SCIENCE BV, 263, 647-649, Mar. 1999, Ultrasonic measurements of LaCoO3 were performed from 4.2 to 600 K. We observed two lattice softenings related to the spin-state transitions of LaCoO3 around 100 and 500 K. The temperature dependence of the elastic modulus is well explained by a model involving three spin states coupled with the lattice. The parameters obtained from the present ultrasonic measurement are in good agreement with those previously obtained from lattice expansion. (C) 1999 Elsevier Science B.V. All rights reserved.
Scientific journal, English - Mechanical responses of helium films adsorbed on two-dimensional mesoporous hectorite
M Hieda; M Suzuki; K Torii; H Yano; N Wada
PHYSICA B-CONDENSED MATTER, ELSEVIER SCIENCE BV, 263, 370-372, Mar. 1999, The mechanical responses of physisorbed films to the vibration of a substrate were investigated by measuring the sound velocity and attenuation of a two-dimensional mesoporous hectorite. The sound velocity of a hectorite pellet adsorbed by both He-4 and He-3 submonolayer films increased drastically at low temperatures accompanied by the attenuation. The most plausible explanation for this behavior is that helium films decouple from the vibrating substrate at low temperatures. (C) 1999 Elsevier Science B.V. All rights reserved.
Scientific journal, English - Elastic anomalies with the spin-state transitions in LaCoO3
S Murata; S Isida; M Suzuki; Y Kobayashi; K Asai; K Kohn
PHYSICA B, ELSEVIER SCIENCE BV, 263, 647-649, Mar. 1999, Peer-reviwed, Ultrasonic measurements of LaCoO3 were performed from 4.2 to 600 K. We observed two lattice softenings related to the spin-state transitions of LaCoO3 around 100 and 500 K. The temperature dependence of the elastic modulus is well explained by a model involving three spin states coupled with the lattice. The parameters obtained from the present ultrasonic measurement are in good agreement with those previously obtained from lattice expansion. (C) 1999 Elsevier Science B.V. All rights reserved.
Scientific journal, English - Elastic anomalies with the spin-state transitions in LaCoO3
S. Murata; S. Isida; M. Suzuki; Y. Kobayashi; K. Asai; K. Kohn
Physica B: Condensed Matter, Elsevier Science Publishers B.V., 263-264, 647-649, 1999, Ultrasonic measurements of LaCoO3 were performed from 4.2 to 600 K. We observed two lattice softenings related to the spin-state transitions of LaCoO3 around 100 and 500 K. The temperature dependence of the elastic modulus is well explained by a model involving three spin states coupled with the lattice. The parameters obtained from the present ultrasonic measurement are in good agreement with those previously obtained from lattice expansion.
Scientific journal, English - Decoupling of He-3 films adsorbed on two-dimensional mesoporous hectorite
M Hieda; M Suzuki; K Torii; H Yano; N Wada
JOURNAL OF LOW TEMPERATURE PHYSICS, SPRINGER/PLENUM PUBLISHERS, 113, 3-4, 363-368, Nov. 1998, The mechanical responses of physisorbed films to the vibration of a substrate were investigated by measuring the sound velocity and attenuation of two-dimensional mesoporous hectorite. The sound velocity of a pellet with adsorbed He-3 films increased drastically at low temperatures accompanied by the attenuation. The temperature dependence of the sound velocity and attenuation can be described by the thermally activated relaxation process, and the increase in sound velocity was found to be proportional to the amount of adsorbed He-3. The most plausible explanation for this behavior is that He-3 films decouple fi om the vibrating substrate at low temperatures.
Scientific journal, English - Surface tension of liquid He-3 under 8 T magnetic field
K Matsumoto; K Ichikawa; S Hasegawa; M Suzuki; Y Okuda
JOURNAL OF LOW TEMPERATURE PHYSICS, PLENUM PUBL CORP, 113, 3-4, 567-572, Nov. 1998, Surface tension of liquid He-3 was measured using the capillary rise method. A 8 T magnetic field teas applied to study the magnetic response. We found that the temperature dependence of the surface tension in 8 T magnetic field was almost the same as that found in zero field by Suzuki et al [Europhysics Letters 5, 333 (1988)]. The surface tension stayed almost constant below 120 mK, whereas it behaved as T-2 in the higher temperature region. The surface tension difference at 8 T field was measured at several temperatures between 30 mK and 100 mK; it decreased by about 350 ppm and no significant temperature dependence was observed within the experimental error The susceptibility near the free surface was found to decrease compared to the bulk. PACS numbers: 67.50.Dg, 68.10.Cr.
Scientific journal, English - Absolute value of the surface tension of liquid He-4
K Nakanishi; M Suzuki
JOURNAL OF LOW TEMPERATURE PHYSICS, PLENUM PUBL CORP, 113, 3-4, 585-590, Nov. 1998, In 1985 line et al. [J. Low, Temp. Phys. 61, 155 (1985)] measured the surface tension of liquid He-4 by the surface-wave resonance method and reported that the surface tension at OK is 354 mu N/m. Recently, Roche et al. [J. Low Temp. Phys. 106, 565 (1997)] obtained the absolute value at 0K to be 375 mu N/m from the dispersion relation of a capillary wave at a micron wavelength. There is a 6%; discrepancy between those two values.
To determine the meniscus effects for the surface waves and the absolute value of the surface tension, we measured the resonance frequencies of the surface wave in two parallelepiped cavities with different widths. By comparing the same wave number of the two cavities, it was found that the resonance frequencies are shifted to be slightly smaller by the meniscus effects. The absolute value of the surface tension, which was obtained by eliminating these effects by using the resonance frequencies of the two cavities, was in agreement with that of line et al. PACS numbers: 68.10.Cr, 67.40.Kh.
Scientific journal, English - Ultrasonic study of the high temperature phase of Fe3O4
S Isida; M Suzuki; S Todo; N Mori; K Siratori
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, PHYSICAL SOC JAPAN, 67, 9, 3125-3129, Sep. 1998, We carried out ultrasonic measurements of the high temperature phase of Fe3O4 under two experimental conditions: (1) applying hydrostatic pressure up to 1.2 GPa and (2) controlling the magnetization direction. In the former experiment, the anomaly of C-44 was suppressed by the application. of pressure, while C-11 was enhanced. However, the normalized pressure dependence of C-11 and C-44 were the same. In the latter, C-11 showed dependence on the relative direction between the magnetization and the sound propagation. We found that the temperature dependence of the extraordinary part of both C-11 and C-44 is well explained by the existence of a deformation unit, which remains up to room temperature. In addition, the observed magnetization direction dependence of C-11 suggests that the deformation of a unit depends on the relative direction between the main axis of a unit and the magnetization direction.
Scientific journal, English - Interfacial tension of phase-separated He-3-He-4 mixtures under pressure
K Ohishi; H Yamamoto; M Suzuki
JOURNAL OF LOW TEMPERATURE PHYSICS, PLENUM PUBL CORP, 112, 3-4, 199-210, Aug. 1998, We measured the irterfacial tension of He-3-He-4 mixtures at several pressures up to 21 am down to 0.18 K as well as the number densities of the He-4-rich and He-3-rich liquids at the phase-separation line. The interfacial tension was proportional to T-2 up, to about 0.4 K without respect to pressure, and the coefficient of this T-2-dependence did not depend strongly on pressure. The extrapolated values of the interfacial tension at absolute zero decreased drastically, to 3 atm, and at this level the decrease about 15 % of the value at the saturated vapor pressure sigma(i) = 23.9 +/- 1.0 mu N/m. However, this tension,vas unchanged above 7 atm. From the pressure dependence of the absolute value the adsorption of He-3 relative to the Gibbs divining surface of He-4 component was calculated.
Scientific journal, English - Stimulated Raman scattering in solid hydrogen: Measurement of coherence decay
JZ Li; M Katsuragawa; M Suzuki; K Hakuta
PHYSICAL REVIEW A, AMERICAN PHYSICAL SOC, 58, 1, R58-R60, Jul. 1998, Stimulated Raman scattering (SRS) is experimentally investigated for solid hydrogen in the context of the strong coupling. Coherence decay behaviors are measured for the Raman transition of Q(0) (nu = 1 - 0) using the time-resolved coherent anti-stokes Raman-scattering method. We show that the coherence decay for the Raman transition changes with the evolution of the SRS from the weak-coupling regime to the strong-coupling regime.
Scientific journal, English - Stimulated Raman Scattering of Solid Hydrogen in the strong-coupling regime: measurement of the coherence decay time
M. Katsuragawa; J.Z. Li; M. Suzuki; K. Hakuta
International Quantum Electronics Conference '98, Technical Digest, QtuG23, San Francisco, USA, 68, May 1998
English - Solid hydrogen for nonlinear optics
M Suzuki; M Katsuragawa; RSD Sihombing; JZ Li; K Hakuta
JOURNAL OF LOW TEMPERATURE PHYSICS, PLENUM PUBL CORP, 111, 3-4, 463-468, May 1998, We recently developed a new method of preparing a parahydrogen crystal which is suitable for experiments on nonlinear optical processes. The crystal was grown slowly from pressurized liquid-phase in order to avoid internal stress from the thermal constriction, and was cooled down to 4.2 K. The obtained crystal was uncracked and perfectly transparent with a high damage threshold. To evaluate the quality, the vibrational coherence decay was measured using the time-resolved coherent anti-Stokes Raman spectroscopy (CARS) technique. The decay process showed a nonexponential behavior, with an asymptotic limit characterized by a single time constant of 2.6 mu s, which corresponds to a linewidth of less than 0.1 MHz. This decay time is extremely slow compared to the previously published work.
Scientific journal, English - Stimulated Raman scattering with strong-coupling in solid hydrogen
M Katsuragawa; M Suzuki; JQ Liang; JZ Li; RSD Sihombing; K Hakuta
JOURNAL OF LOW TEMPERATURE PHYSICS, PLENUM PUBL CORP, 111, 3-4, 497-502, May 1998, It is shown through stimulated Raman scattering in parahydrogen crystal that strongly coupled dressed states on the field-matter interacting system are established in the far off-resonant condition, and that the phase-matching for the parametric anti-Stokes generation process is realized without strict restriction of the medium refractive index dispersion.
Scientific journal, English - Nonlinear Optics in Solid Hydrogen
K. Hakuta; M. Katsuragawa; M. Suzuki; R. S; D. Sihombing; J.Z. Li
Laser Application to Muon Science, Ibaragi, Japan, 115-121, Mar. 1998
English - Stimulated Raman Scattering in Solid Hydorogen
J. Z. Li; M. Katsurakgawa; M. Suzuki; K. Hakuta
Measurement of Coherence Decay, Phys. Rev. A, 58, 1, R58-R60, 1998
English - Nonlinear optics in solid hydrogen
M Katsuragawa; M Suzuki; RSD Sihombing; JZ Li; K Hakuta
LASER AND PARTICLE BEAMS, CAMBRIDGE UNIV PRESS, 16, 4, 641-648, 1998, We show through experiments of stimulated Raman scattering how solid hydrogen (parahydrogen) can open new perspectives on nonlinear optics. Two phenomena are described: One is the self-induced phase matching in parametric anti-Stokes stimulated Raman scattering (SRS) in which the phase matching is self-organized automatically without the stringent restriction of refractive-index dispersion of the medium, and the other is the extremely slow coherence decay behavior for the Raman transition that may result in the Raman width of 80 Wt full width at half maximum (FWHM).
Scientific journal, English - Interfacial tension of phase-separated He-3-He-4 mixtures under pressure
K Ohishi; H Yamamoto; M Suzuki
JOURNAL OF LOW TEMPERATURE PHYSICS, PLENUM PUBL CORP, 110, 1-2, 703-708, Jan. 1998, We measured the interfacial tension of He-3-He-4 mixtures under pressure of 21 atm down to about 0.2K by using the resonance of the interfacial wave and found that the decrease from absolute zero is proportional to T-2 up to about 0.4K From the simple extrapolation of this T-2-dependence the interfacial tension at absolute zero is obtained as sigma(i)(0) = 19.3 +/- 1.3 mdyne/cm. Compared with saturated vapor pressure, the interfacial tension at absolute zero decreases by about 20%, and the coefficient of the T-2-dependence does not depend strongly on pressure. The large T-2-dependence both at saturated vapor pressure and at 21 atm may be attributable to the change in density difference between the two phases.
Scientific journal, English - Nonlinear optics in solid hydrogen
M Katsuragawa; M Suzuki; RSD Sihombing; JZ Li; K Hakuta
LASER AND PARTICLE BEAMS, CAMBRIDGE UNIV PRESS, 16, 4, 641-648, 1998, We show through experiments of stimulated Raman scattering how solid hydrogen (parahydrogen) can open new perspectives on nonlinear optics. Two phenomena are described: One is the self-induced phase matching in parametric anti-Stokes stimulated Raman scattering (SRS) in which the phase matching is self-organized automatically without the stringent restriction of refractive-index dispersion of the medium, and the other is the extremely slow coherence decay behavior for the Raman transition that may result in the Raman width of 80 Wt full width at half maximum (FWHM).
Scientific journal, English - Dark-state coherence and stimulated Raman scattering in solid hydrogen
K Hakuta; M Katsuragawa; M Suzuki
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES, ROYAL SOC, 355, 1733, 2405-2408, Dec. 1997, We show through the experiments of stimulated Raman scattering in solid hydrogen that a strongly coupled dressed state, dark state, is spontaneously established as the eigenstate of the field-matter interacting system, and that in terms of the parametric anti-Stokes generation process the phase matching is self-induced as a consequence of the establishment of the dark state.
Scientific journal, English - He-3 impurity effects on the growth kinetics of He-4 crystals
M Suzuki; M Thiel; P Leiderer
JOURNAL OF LOW TEMPERATURE PHYSICS, PLENUM PUBL CORP, 109, 1-2, 357-367, Oct. 1997, We report the growth kinetics of the He-4 crystals with a small amount of He-3 impurities around 0.8 K. The growth resistance was measured using the response of the charged interface with respect to an externally applied voltage. In 5 ppm and 10 ppm He-3 mixtures, it is found that (1) the relaxation process can be expressed as an exponential behavior, (2) the growth resistance becomes larger compared to pure He-4 and does not have a strong He-3 concentration dependence, and (3) the temperature dependence of the growth resistance is much the same as pure He-4. We discuss several possible explanations of the present experiment.
Scientific journal, English - Stimulated Raman Scattering with Strong-Coupling in Solid Hydrogen, Second International Conference on Cryocrystals and Quantum Crystals
M. Katsuragawa; M. Suzuki; J. Q. Liang; J.Z. Li; R. S; D. Sihombing; K. Hakuta
Abstracts and Programme, P2-3, Polanica-Zdroj, Poland, 2-3, Sep. 1997
English - Solid Hydrogen for Nonlinear optics, Second International Conference on Cryocrystals and Quantum Crystals
M. Suzuki; M. Katsuragawa; R. S; D. Sihombing; J.Z. Li; K. Hakuta
Abstracts and Programme, J-S19, Polanica-Zdroj, Poland, Sep. 1997
English - Parametric Anti-Stokes Stimulated Raman Scattering under Strong-Coupling Condition
M. Katsuragawa; J. Q. Liang; J.Z. Li; M. Suzuki; K. Hakuta
CLEO/Pacific Rim '97, Technical Digest, ThM4, Makuhari, 225, Jul. 1997
English - Self-induced phase matching in parametric anti-stokes stimulated Raman scattering
K Hakuta; M Suzuki; M Katsuragawa; JZ Li
PHYSICAL REVIEW LETTERS, AMERICAN PHYSICAL SOC, 79, 2, 209-212, Jul. 1997, We show through the experiments of parametric anti-Stokes stimulated Raman scattering for solid hydrogen that the phase matching in a parametric process can be self-induced without the stringent restriction of the medium. We explain this self-induced phase matching as a consequence of strong coupling between radiation fields and medium spontaneously established through the stimulated Raman scattering process.
Scientific journal, English - Interfacial tension of phase-separated H-3-He-4 mixtures at saturated vapor pressure
A Sato; K Ohishi; M Suzuki
JOURNAL OF LOW TEMPERATURE PHYSICS, PLENUM PUBL CORP, 107, 1-2, 165-173, Apr. 1997, The interfacial tension of He-3-He-4 mixtures at saturated vapor pressure has been measured precisely down to 0.15 K by means of the resonance of the interfacial wave. We found that the decrease of the interfacial tension from the value at absolute zero can be described as 56.8T(2) mdyne/cm up to about 0.4 K and that the extrapolated value at absolute zero is 23.9+/-1.0 mdyne/cm. The large temperature dependence in the low temperature region may be explained by the effect of the change in density difference between the two phases.
Scientific journal, English - Pressure dependence of the 100 K spin-state transition in LaCoO3
K Asai; O Yokokura; M Suzuki; T Naka; T Matsumoto; H Takahashi; N Mori; K Kohn
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, PHYSICAL SOC JAPAN, 66, 4, 967-970, Apr. 1997, The pressure dependence of the 100 K spin-state transition in LaCoO3 is investigated through magnetization measurement under pressures of up to 18.2 kbar. The energy gap, Delta, between the low-spin ground state and the excited magnetic state (intermediate spin) increases remarkably with increasing pressure. The linear part of the pressure dependence of Delta, which is dominant below 5 kbar, is interpreted consistently by the volume expansion due to the spin-state transition under ambient pressure. In the higher pressure region, a quadratic pressure dependence is dominant, which suggests a Very steep volume dependence of the energy of the excited magnetic state under the highly compressed condition.
Scientific journal, English - 3He Impurity Effects on the Growth Kinetics of 4He Crystal
Journal of Low Temperature Physics, 109, 1, 2,357, 1997
Scientific journal, English - The Royal Society
K. Hakuta; M. Katsuragawa; M. Suzuki
Discussion Meeting, Highlights in Quantum Optics, at The Royal Society, London, U. K. Invited Paper, Jan. 1997
English - Lock-in amplifier with autotracking bandpass filter
A Sato; A Ohara; Y Ogawa; M Suzuki
REVIEW OF SCIENTIFIC INSTRUMENTS, AMER INST PHYSICS, 67, 11, 4021-4022, Nov. 1996, A simple, low-cost lock-in amplifier was described. This system has an autotracking bandpass filter which synchronizes its center frequency automatically with the reference frequency (C) 1996 American Institute of Physics.
Scientific journal, English - Pressure effect on the elastic constants of magnetite
S Isida; M Suzuki; S Todo; N Mori; K Siratori
PHYSICA B-CONDENSED MATTER, ELSEVIER SCIENCE BV, 219-20, 638-640, Apr. 1996, In order to investigate the low temperature transition of magnetite (Fe3O4) around T-v similar to 123 K, the longitudinal sound velocity has been measured above T-v under hydrostatic pressures Lip to 12 kbar. We observed that the sound velocity nu([110]) shows no pressure dependence, while the elastic constant C-11, which is calculated from nu([100]), has a large softening with increasing pressure below 250 K. The amount of softening of C-11 by applying pressure seems to obey the Curie-Weiss law with theta approximate to 120 K except near T-v.
Scientific journal, English - Acoustic phonon dispersion of SiO2 (quartz) near the incommensurate phase transition
S Ishibashi; K Abe; M Suzuki; Y Sasaki; T Shigenari
PHYSICA B-CONDENSED MATTER, ELSEVIER SCIENCE BV, 219-20, 593-595, Apr. 1996, Acoustic phonons in quartz were studied by Brillouin, ultrasonic and piezoelectric resonance methods. The dispersion of LA phonons in the incommensurate (INC) phase can be interpreted by a single relaxation mechanism. A TA phonon (c(66)) shows a small anomaly at the INC transition temperature and it critically changes near the lock-in transition from INC to alpha-phase. The fluctuation effects of the soft TA-Sigma branch phonon on the sound velocity were found to be much less than those in other crystals.
Scientific journal, English - Interfacial tension of phase-separated He-3-He-4 mixtures
A Sato; K Ohishi; M Suzuki
CZECHOSLOVAK JOURNAL OF PHYSICS, CZECHOSLOVAK JNL OF PHYSICS, 46, 197-198, 1996, The interfacial tension of phase-separated He-3-He-4 mixtures has been measured precisely by means of the resonance of the interfacial wave down to 0.15K. We found that the decrease of the interfacial tension from the value at 0K under saturated vapor pressure can be described as 56.8T(2) mdyne/cm up to about 0.4K and that the extrapolated value at 0K is 23.9+/-1.0 mdyne/cm. Compared to the surface tension of liquid He-3, the interfacial tension has a large temperature dependence al low temperatures, which is explained as due to the change of the He-4-rich liquid density.
Scientific journal, English - He-3 impurity effects on the growth kinetics of He-4 crystals
M Suzuki; M Thiel; P Leiderer
CZECHOSLOVAK JOURNAL OF PHYSICS, CZECHOSLOVAK JNL OF PHYSICS, 46, 459-460, 1996, We report on the growth kinetics of He-4 crystals with a small amount of He-3 impurities around 0.8K. The growth resistance was measured using the response of the charged liquid-solid interface with respect to an externally applied voltage. In 5ppm and 10ppm He-3 mixtures, it is found that (1) the relaxation process can be expressed as an exponential behavior, (2) the growth resistance becomes larger compared to pure He-4 and does not have a strong He-3 concentration dependence, and (3) the temperature dependence of the growth resistance is much the same as for pure He-4. We discuss several possible explanations of the present experiment.
Scientific journal, English - Superfluidity of He-4 in two-dimensional mesopores of hectrite
M Ilieda; M Suzuki; H Yano; N Wada
CZECHOSLOVAK JOURNAL OF PHYSICS, INST PHYSICS ACAD SCI CZECH REPUBLIC, 46, 129-130, 1996, In two-dimensional mesopores of hectrite that have an open spacing of 17-20 Angstrom between framework layers, the superfluidity of He-4 was studied by means of ultrasound of 10MHz. At the full adsorption, we found that the sound velocity increases at about 1.8K with decreasing temperature, which corresponds to the superfluid transition To in mesopores of hectrite. The decrease of T-0 from the lambda temperature is believed to be the size effect of the mesopores on the coherence length.
Scientific journal, English - SURFACE-TENSION AND MASS DENSITY OF DILUTE-SOLUTIONS OF HE-4 IN HE-3
A SATO; M SUZUKI
JOURNAL OF LOW TEMPERATURE PHYSICS, PLENUM PUBL CORP, 99, 5-6, 727-744, Jun. 1995, We report the first precise measurement on the surface tension of dilute solutions of He-4 in He-3 from 2.6 K to the phase separation temperature as well as the mass density of the solutions. Compared to liquid He-3, the surface tension of dilute He-4 solutions increases by 3.5 +/- 0.1 mdyne/cm for 2.5% He-4 and 7.4 +/- 0.2 mdyne/cm for 5.2% He-4 at 1 K. The increase of the surface tension means a negative adsorption, i.e., He-4 atoms ave excluded from the free surface. The surface adsorption, which is calculated on the basis of the He-4 quasiparticle model, was compared with the data. Assuming that the effective potential near the surface for the He-4 quasiparticle is long-range, the temperature dependence of the surface adsorption is well explained.
Scientific journal, English - Ultrasonic Investigation of a Two-Dimensional Trianular Lattice Ferrimagnet, ErFe2O4-8 Single Crystal
Journal of the Physical Society of Japan, 64, 6, 214, 1995
Scientific journal, English - Ultrasonic Investigation of a Two-Dimensional Triangular Lattice Ferrimagnet, ErFe2O4−δ Single Crystal
Hijiri Kito; Susumu Isida; Masaru Suzuki; Jun Akimitsu; Shunji Takekawa; Kiiti Siratori; Kiiti Siratori
Journal of the Physical Society of Japan, 64, 6, 2147-2151, 1995, Velocities and attenuations of longitudinal sound waves were measured at 100 MHz for a single crystal of non-stoichiometric ErFe2O4−δ, along the 〈0, 0, 1〉 and 〈1, 1, 0〉 axes in the hexagonal frame, below 300 k. At room temperature, velocities were 5.22 × 103 and 5.49 × 103 m/s along the 〈0, 0, 1〉 and 〈1, 1, 0〉 axes, respectively. These values correspond to the elastic constants of C11 = 1.94 × 1012 dyne/cm2 and C33 = 1.75 × 1012 dyne/cm2. Slight softening was disclosed along the 〈0, 0, 1〉 axis at around 240 k. Correspondingly, a large peak was observed in the attenuation. These anomalies are attributed to the emergence of two-dimensional spin ordering in this crystal at this temperature. On the contrary, no anomaly was detected along the 〈1, 1, 0〉 axis at around 240 k, with rather high attenuation level almost independent of temperature. This absence of anomalies was discussed on the existence of three kinds of magnetic domains. Development of the correlation of Er spins was suggested below 30 k. © 1995, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.
Scientific journal, English - ACOUSTIC-PHONON DISPERSION IN THE INCOMMENSURATE PHASE OF SIO2 (QUARTZ)
E TANAKA; S ISHIBASHI; K ABE; M SUZUKI; T SHIGENARI
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, PHYSICAL SOC JAPAN, 64, 1, 136-141, Jan. 1995, Ultrasonic and Brillouin scattering measurements were performed near the incommensurate (INC) transition of SiO2 (quartz). The decrease of the LA sound velocity in the INC phase was found to be much less for 10 MHz than for 27 GHz, being remarkably different from other crystals which undergo INC phase transitions. The dispersion in the INC phase can be well characterized by a simple Landau-Khalatnikov type relaxation with a relaxation time tau(T) = (2.6 +/- 0.5) x 10(-12) (T-i - T)(-1) s. A small but critical decrease of the TA velocity as T --> T-c(= T-i - 1.4 K) was also detected by the ultrasonic measurement.
Scientific journal, English - Surface Tension of Dilute Solutions of 4He in 3He
Physica B, 194-196, 387, 1994
Scientific journal, English - ANOMALOUS PINNING OF PT-DOPED SINGLE CRYSTALLINE LA1.88SR0.12CUO4 STUDIED BY ULTRASOUND
M SUZUKI; Y SATO; Y KASHIWAGI; Y OKUDA; Y HIDAKA
PHYSICA C, ELSEVIER SCIENCE BV, 208, 3-4, 333-338, Apr. 1993, The longitudinal sound velocity of the single crystalline La1.88gSr0.12CuO4 was measured in order to examine the vortex dynamics in the mixed state. The sample was grown by the flux method in a platinum crucible. A longitudinal wave with a frequency of 200 MHz was propagated along both the c-axis and the a-axis under a magnetic field up to 14 T. For the perpendicular arrangement (k parallel-to the c-axis and B parallel-to the Cu-O plane), the sound velocity enhancement due to the motion of pinned flux lines was below T(c). The enhancement is in good agreement with the empirical Arrhenius form. The enhancement was also observed for the parallel arrangement (k parallel-to the a-axis and B parallel-to the Cu-O plane), although the flux lines are not expected to couple with the longitudinal sound wave in a simple model.
Scientific journal, English - SURFACE-TENSION OF LIQUID-N2 NEAR THE LIQUID-VAPOR CRITICAL-POINT
A SHIMOYANAGITA; N ITAGAKI; A SATO; M SUZUKI
PHYSICA B, ELSEVIER SCIENCE BV, 165, 165-166, Aug. 1990
Scientific journal, English - ACOUSTIC MICROSCOPE USING PRESSURIZED SUPERFLUID HE-4
K KARAKI; M SUZUKI; Y OKUDA
JOURNAL OF APPLIED PHYSICS, AMER INST PHYSICS, 67, 4, 1680-1683, Feb. 1990, Peer-reviwed
Scientific journal, English - SOUND-VELOCITY ANOMALY OF YBA2CU3OY
M SUZUKI; Y OKUDA; IWASA, I; AJ IKUSHIMA; T TAKABATAKE; Y NAKAZAWA; M ISHIKAWA
PHYSICA C, ELSEVIER SCIENCE BV, 153, 266-267, Jun. 1988
Scientific journal, English - SURFACE-TENSION OF LIQUID-HE-3 FROM 0.4 K DOWN TO 15 MK
M SUZUKI; Y OKUDA; AJ IKUSHIMA; M IINO
EUROPHYSICS LETTERS, EDITIONS PHYSIQUE, 5, 4, 333-337, Feb. 1988
Scientific journal, English - SURFACE-TENSION OF LIQUID-HE-4 AND HE-3
AJ IKUSHIMA; M IINO; M SUZUKI
CANADIAN JOURNAL OF PHYSICS, NATL RESEARCH COUNCIL CANADA, 65, 11, 1505-1509, Nov. 1987, Peer-reviwed
Scientific journal, English - SOUND-ATTENUATION IN HE-3-HE-4 LIQUID-MIXTURES UNDER PRESSURE
FUJII, I; AJ IKUSHIMA; M FUKUHARA; K KANEKO; M SUZUKI
JOURNAL OF LOW TEMPERATURE PHYSICS, PLENUM PUBL CORP, 63, 5-6, 535-551, Jun. 1986, Peer-reviwed
Scientific journal, English - SURFACE-TENSION OF LIQUID-HE-3 AND HE-4 NEAR THE LIQUID GAS CRITICAL-POINT
M IINO; M SUZUKI; AJ IKUSHIMA
JOURNAL OF LOW TEMPERATURE PHYSICS, PLENUM PUBL CORP, 63, 5-6, 495-506, Jun. 1986, Peer-reviwed
Scientific journal, English - SURFACE-TENSION OF LIQUID-HE-4 NEAR T-LAMBDA
M SUZUKI; M IINO; AJ IKUSHIMA
JOURNAL OF LOW TEMPERATURE PHYSICS, PLENUM PUBL CORP, 63, 1-2, 129-137, Apr. 1986, Peer-reviwed
Scientific journal, English - SURFACE-TENSION OF LIQUID-HE-4 - SURFACE-ENERGY OF THE BOSE-EINSTEIN CONDENSATE
M IINO; M SUZUKI; AJ IKUSHIMA
JOURNAL OF LOW TEMPERATURE PHYSICS, PLENUM PUBL CORP, 61, 1-2, 155-169, 1985, Peer-reviwed
Scientific journal, English - SURFACE-TENSION OF LIQUID-HE-3 DOWN TO 0.3-K
M IINO; M SUZUKI; AJ IKUSHIMA; Y OKUDA
JOURNAL OF LOW TEMPERATURE PHYSICS, PLENUM PUBL CORP, 59, 3-4, 291-304, 1985, Peer-reviwed
Scientific journal, English
MISC
- 10aAS-11 Phonon Dispersion Curve of Dissipation Energy during Friction Process on MoS_2(0001) surface
Ishikawa Makoto; Suzuki Masaru; Sasaki Naruo; Miura Kouji
The Physical Society of Japan (JPS), 22 Aug. 2014, Meeting abstracts of the Physical Society of Japan, 69, 2, 676-676, Japanese, 1342-8349, 110009874297, AA11439205 - 24pBD-15 Interface friction of Kr films adsorbed on synthetic single-crystalline mica substrate II
Kobayashi H.; Taniguchi J.; Suzuki M.; Arakawa I.
The Physical Society of Japan, 2012, Meeting Abstracts of the Physical Society of Japan, 67, 0, 308-308, Japanese, 1342-8349, 110009565931, AA11439205 - 27pTF-3 Interface friction of Xe films adsorbed on single-crystalline graphite substrate
Kobayashi H.; Taniguchi J.; Suzuki M.; Miura K.; Arakawa I.
The Physical Society of Japan, 2011, Meeting Abstracts of the Physical Society of Japan, 66, 0, 333-333, Japanese, 1342-8349, 110008610919, AA11439205 - 24aTF-8 Sliding friction of Kr films adsorbed on single-crystalline graphite substrate
Kobayashi H.; Taniguchi J.; Suzuki M.; Miura K.; Arakawa I.
The Physical Society of Japan, 2010, Meeting Abstracts of the Physical Society of Japan, 65, 0, 233-233, Japanese, 1342-8349, 110008097323, AA11439205 - 25pQC-7 Sliding friction of Kr films adsorbed on single-crystalline graphite substrate
Kobayashi H.; Taniguchi J.; Suzuki M.; Miura K.; Arakawa I.
The Physical Society of Japan, 2009, Meeting Abstracts of the Physical Society of Japan, 64, 0, 164-164, Japanese, 1342-8349, 110007496556, AA11439205 - 21aVB-3 Sliding friction of Kr films adsorbed on single-crystalline graphite substrate
Kobayashi H.; Taniguchi J.; Suzuki M.; Miura K.; Arakawa I.
The Physical Society of Japan, 2008, Meeting Abstracts of the Physical Society of Japan, 63, 0, 208-208, Japanese, 1342-8349, 110006983153, AA11439205 - 25pWF-13 Sliding friction of Kr films adsorbed on single-crystalline graphite substrate
Kobayashi H.; Taniguchi J.; Suzuki M.; Miura K.; Arakawa I.
The Physical Society of Japan, 2008, Meeting Abstracts of the Physical Society of Japan, 63, 0, 316-316, Japanese, 1342-8349, 110007196322, AA11439205 - 20pTC-14 Interfacial Friction of Kr films Adsorbed on Graphite
Ohta K.; Ueda Y.; Taniguchi J.; Suzuki M.; Arakawa I.
The Physical Society of Japan, 2007, Meeting Abstracts of the Physical Society of Japan, 62, 0, 356-356, Japanese, 1342-8349, 110007193340, AA11439205 - "固体水素を用いた新しい光学過程"
桂川眞幸; 百瀬孝昌; 鈴木 勝; 是枝聡肇; 白田耕藏
2001, 光学, 30, 2, 111-116, Japanese, Introduction other - "吸着膜の摩擦"
鈴木 勝
アグネ技術センタ-, 2000, 固体物理, 35, 10, 845-851, Japanese, Introduction other, 0454-4544, 40001389866, AN00092629 - 31p-YR-12 Anomalous dispersion of acoustic phonon in the incommensurate phase of SiO_2 (Quartz)
Tanaka E; Ishibashi S; Abe K; Sasaki Y; Shigenari T; Suzuki M
The Physical Society of Japan (JPS), 16 Mar. 1994, Abstracts of the meeting of the Physical Society of Japan. Annual meeting, 49, 2, 113-113, Japanese, 110002162667, AN10451127
Books and other publications
- 物理を教える -物理教育研究と実践に基づいたアプローチ-
並木雅俊監訳; 興治文子; 鈴木勝; 副島雄児; 谷口和成; 安田淳一郎; 山本隆夫訳
Japanese, Joint translation, 第10,11,12,13,14章, 丸善出版, 28 Feb. 2017 - 物理学演習
阿部 浩二; 奥野 剛史; 中村 仁; 細見 斉子
Japanese, Joint work, 編著, 培風館, Apr. 2012 - 科学をどう教えるか
Japanese, Joint translation, 監訳者, 丸善, 2012 - 高圧技術ハンドブック
毛利信男; 村田恵三; 上床美也; 高橋博樹
Japanese, Joint work, 丸善, Jan. 2007 - 「実験物理学講座６：磁気測定 I 」
Japanese, Joint work, 丸善, 2000 - 「応用物理データブック」
Japanese, Joint work, 丸善, 1994
Lectures, oral presentations, etc.
- ナノスコピック系の摩擦の物理：摩擦の素過程と制御 「表面吸着系の摩擦の素過程と制御」
鈴木 勝
Invited oral presentation, Japanese, ２００７年春季大会, 日本物理学会
Mar. 2007 - グラファイト基板上のHe膜のスリップ現象II
小倉寿人; 細見斉子; 鈴木勝
Oral presentation, Japanese, 日本物理学会第５８回年次大会
Mar. 2003 - HoNi_2_B_2_C単結晶の電気伝導
木村敏昭; 鈴木勝; 黒木和彦; 石田進; 竹屋浩幸
Oral presentation, Japanese, 日本物理学会２００２年秋季大会
Sep. 2002 - グラファイト基板上のHe膜のスリップ現象
細見斉子; 小倉寿人; 鈴木勝
Oral presentation, Japanese, 日本物理学会２００２年秋季大会
Sep. 2002 - "高密度励起下におけるコヒーレントバイブロンの位相緩和"
桂川 眞幸; Fam Le Kien; 鈴木 勝; 白田 耕藏
Oral presentation, Japanese, 日本物理学会 2001年秋季大会（徳島）
Sep. 2001 - "固体水素における第一振動励起状態のエネルギー緩和"
J. Z. Li; 鈴木 勝; 桂川 眞幸; 白田 耕藏
Oral presentation, Japanese, 日本物理学会 2001年秋季大会 (徳島)
Sep. 2001 - "La_1-x_Sr_x_CoO_3_(x=0,0.1) パルス強磁場における磁化と磁歪"
佐藤圭輔; 後藤恒昭; 小林義彦; 鈴木勝; 浅井吉蔵
Oral presentation, Japanese, 日本物理学会 2001年秋期大会 (徳島)
Sep. 2001 - "グラファイト基板上のHe膜のスリップ現象"
小倉 寿人; 檜枝 光憲; 鈴木 勝
Oral presentation, Japanese, 日本物理学会 2001年秋期大会 (徳島)
Sep. 2001 - "He吸着膜のスリップ現象における不純物効果"
渡邊 武晴; 檜枝 光憲; 鈴木 勝; 和田 信雄
Oral presentation, Japanese, 日本物理学会 2001年秋期大会 (徳島)
Sep. 2001 - "HoNi2B2Cの超音波測定"
末武美樹; 高橋洋子; 鈴木 勝; 石田 進; 竹屋浩幸
Oral presentation, Japanese, 日本物理学会 第56回年次大会 (東京)
Mar. 2001
Research Themes
- 水晶マイクロバランスによる3He固体膜と4He固体膜の力学応答の研究
鈴木勝
01 Apr. 2021 - 31 Mar. 2024 - 量子モンテカルロ法を用いた低次元ヘリウム系における新奇な量子物性の研究
平島 大
01 Apr. 2021 - 31 Mar. 2024 - Superlubric control using structural change by compression of molecular bearing interface
Sasaki Naruo
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, The University of Electro-Communications, Grant-in-Aid for Scientific Research (B), The compression response characteristics of graphene/C60/graphene interface nanostructures was discussed. First, we focused on the compressive properties of the nanostructure in which a single C60 molecule is sandwiched between graphene sheets. Comparing the effective spring constant of the entire interface system with those of single C60 and of C60-graphene interlayer, it was clarified that the C60/graphene interface system can be regarded as a series spring of C60 single molecule spring and C60-graphene interlayer spring. Next, we focused on the graphene sheet, which is a component of the interface structure, and we developed an effective potential function that coarse-grained the Tersoff potential function, which represents a covalent bond. As a result, we succeeded in increasing the calculation speed of graphene adhesion to 10,000 times that of the conventional Tersoff function., 17H02785
01 Apr. 2017 - 31 Mar. 2020 - 摩擦制御を目指したナノ滑りでのエネルギー散逸の研究
01 Apr. 2017 - 31 Mar. 2020 - Nanomechanics of pi-figurated molecular machines
Sasaki Naruo; MIURA KOUJI; ITAMURA NORIAKI; SUZUKI MASARU
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, The University of Electro-Communications, Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area), Elucidation of nanomechanics of π-figurated molecular machine and proposal of precise measurement method have been performed as follows: We developed a model potential suitable for high-speed simulation of friction at the graphene interface, and succeeded in reducing the calculation time to about 1 / 10,000 of the previous one. We proposed a color AFM method to convert tip-surface interaction information into RGB color data and visualize it. We also proposed tribo-phonon spectroscopy (TPS) to detect energy dissipation dynamically using QCM-AFM. The polymer solution containing carbon nanotubes was stretched using a microfluidic device in order to produce a new cell scaffolding material. The compression and friction properties of the sumanene thin film adsorbed on the gold surface were evaluated by molecular dynamics method., 26102016
10 Jul. 2014 - 31 Mar. 2019 - Superlubric control of fullerene molecular bearings using graphene curvature
Sasaki Naruo; MIURA KOUJI; SUZUKI MASARU; ITAMURA NORIAKI
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, The University of Electro-Communications, Grant-in-Aid for Scientific Research (B), In order to investigate the influence of graphene curvature on superlubricity, molecular mechanics simulation of peeling process of monolayer graphene sheet adsorbed onto the graphite substrate was carried out. As the initial orientation angle of the graphene adsorption is varied little by little from the AB stacking orientation, the effect of lattice mismatch of the surface contact area appears, and the mean lateral force during the surface contact process markedly decreases to about 0 pN for the orientation angle of 9 deg. For larger orientation angle, the mean lateral force changed only slightly around 0 pN., 26286053
01 Apr. 2014 - 31 Mar. 2017 - エネルギー散逸像とトポ像の同時測定による動摩擦機構の解明
01 Apr. 2014 - 31 Mar. 2017 - Design of Friction-Controllable Fullerene Molecular Bearing Systems
SASAKI Naruo; MIURA Kouji; SUZUKI Masaru; ITAMURA Noriaki
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Seikei University, Grant-in-Aid for Scientific Research (B), Superlubricity of C60/graphene and graphene/graphene interfaces is studied by molecular mechanics simulation. First, for superlubricity of (graphene)n/C60/(graphene)n interface, difference between multilayer (n>1) and monolayer (n=1) systems are found. For monolayer, superlubricity is derived from only stacking relation between C60 and graphene. However, for multilayer, superlubricity is also derived from that between graphene and graphene, which opens an lower energy path. Next, it is found by theory and experiment that, for peeling and adhesion of graphene sheet, quasiperiodic lateral force curve is obtained due to stick-slip motion during surface contact region, whose period nearly corresponds to the lattice constant of graphite., 23360023
01 Apr. 2011 - 31 Mar. 2014 - Quantum Manipulation of Nuclear Spin of Ortho-H2 Molecule in Solid Hydrogen
HAKUTA Kohzo; SUZUKI Masaru; KATSURAGAWA Masayuki
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, The University of Electro-Communications, Grant-in-Aid for Scientific Research (B), We carried out the researches to establish a basis for manipulating nuclear-spin quantum-coherence of ortho-hydrogen molecule in solid hydrogen. Simultaneously, we developed a method to manipulate optical processes using optical nanofiber ; it was originally proposed to introduce a strong light into the solid hydrogen. Regarding the ortho-hydrogen project, we developed a highly-stable single-frequency cw laser at 2.4 μm wavelength using doubly-resonant OPO-technique. Ortho-hydrogen infrared transition (v=1-0, J=1-1) was measured systematically. We showed that the transition reveals an ultra-narrow spectral width of 1.6 MHz HWHM. This width is the narrowest width observed just using simple absorption spectroscopy, without using any nonlinear laser-spectroscopic method. Although density of ortho-hydrogen is very low 40 ppm, the peak absorption of 1-cm solid hydrogen crystal reaches to 60% ; it is due to the ultra-narrow spectral feature. We demonstrated also that the vibration-rotation spectrum splits into three components with splittings of about 10 MHz. The origin of the splitting may be understood due to breaking of magnetic degeneracy of J=1 state into three sublevels via crystal field. The observations have demonstrated that the ortho-hydrogen embedded in solid-parahydrogen is a unique system for realizing quantum coherence control in solid. The observed degeneracy breaking may open a new possibility to realize a new Raman three level scheme without magnetic field. Regarding the nanofiber, we established a method to produce nanofibers with diameter from 1μm to 400 nm with transmission of 80%. We showed theoretically a unique possibility to develop optical processes using nanofibers, very different from those in free space ; a key point is to confine both optical field and atoms/molecules into a submicron space around a nanofiber. We can manipulate single atom/molecule transition just using single photon. Moreover, spontaneous emission of atom/molecule near the nanofiber is strongly modified to emit photons into a guided mode of a nanofiber. We have observed experimentally the unique features of confinement in February of 2006. The observations imply that the nanofiber technique may open a new category of quantum optics., 15340131
2003 - 2005 - Lattice anomaly associaterd with the magnetic order in a re-entrant superconductor Ho_<1-x>Y_xNi_2B_2C
ASAI Kichizo; SUZUKI Masaru; KOBAYASHI Yoshihiko
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, The University of Electro-Communications, Grant-in-Aid for Scientific Research (C), In RNi_2B_2C(R=rare earth elements) the superconductivity and the magnetic order of the rare-earth elements coexist, (or compete), where the superconductivity, the magnetism, and the lattice dynamics are closely related to the others. When RE =Ho, the superconducting transition temperature (Tc=7K) is close to the magnetic transition temperature (T_N=5K), and the temperature vs magnetic-field phase diagram for the superconductivity and the magnetism is complicated involving the reentrant superconducting phase and antiferro-, ferri-, ferro-, and incommensurate magnetic phases. The purpose of the present project is to elucidate the interrelation between the superconductivity and the magnetism of HoNi_2B_2C through "lattice" by the ultrasonic measurement and by lattice deformation under uniaxial stresses. We carefully checked the sample dependence of the superconductivity of the single crystals prepared by a froating-zone infraned furnace, and found that multiple superconducting phases often coexist even in a single crystal. The Ultrasonic measurements revealed that the elastic constant C_<66>, relevant to the strain along [110], shows a large softening up to 60% with decreasing temperature from 80 K to T_N. We conclude that the strain couples with the ferromagnetic fluctuation of Ho magnetic moments within the c-plane. The elastic constant C_<33>, relevant to the strain along [001], shows a similar softening with decreasing temperature from 80 K to T_N although its change is smaller by two orders of magnitude than C_<66>. In addition, C_<33> shows stepwise softenings associated with the meta-magnetic transitions at 2 K. We conclude that the strain along [001] couples with the magnetic correlation of Ho magnetic moments between the c-planes. We deduced the dependence on the c-spacing of the exchange interactions between the c-planes. The magnetic measurements under uniaxial stress revealed that T_N increases remarkably by applying a stress along [110]. The rate is larger by 1 order of magnitude than that in the hydro-pressure. On the other hand, T_N dose not change by the stress along [001] within the present precision. We did not find any appreciable change of Tc by the stresses in all directions. In addition to the above investigation, we performed preliminary x-ray magnetic scattering experiment using synchrotron radiation in Spring-8. We confirmed the periodicity of the antiferro- and ferri- magnetic phases at 2 K by magnetic Bragg scattering., 14540331
2002 - 2003 - スピン状態と結合した格子揺らぎ
浅井 吉蔵; 近 桂一郎; 小林 義彦; 鈴木 勝
日本学術振興会, 科学研究費助成事業, 電気通信大学, 特定領域研究, 酸化物中八面体位置を占めるCo^<3+>(3d)^6の中間スピン状態(S=1,以後IS)は、低スピン(S=0,以後LS)、及び高スピン状態(S=2,以後HS)に比べてエネルギーが高く、通常実現することはないと考えられていたが、近年、LaCoO_3では100K近傍から半導体-金属転移の起こる500Kまでの広い温度範囲でIS状態が主たるスピン状態であるという提案がなされている。本研究では、(1)LS-ISスピン転移の動的性質とIS電子状態の軌道状態を明らかにし、(2)LaCoO_3中でIS状態が安定化される原因を探るために、(A)単一ドメインのLaCoO_3単結晶を用いて超音波測定を行い、(B)La_<1-x>Ca_xCoO_3の電子物性を調べた。 (A)では、赤外線集中加熱炉で育成した擬立方晶のLaCoO_3単結晶(4つの菱面晶結晶ドメインからなる)の[111]軸方向に圧力を加えて、1500℃から1300℃までstress annealingを行い、単一ドメインの単結晶を得ることに成功した。その試料で菱面晶系[111]軸方向の10MHz縦波超音波測定を行い、100K転移に伴う格子のソフト化を観測した。多ドメイン試料の擬立方晶[111]軸方向の実験結果に比べて、ソフト化の程度が大きく、スピン転移に伴う弾性以上が実際に菱面晶の対称性を持つことがわかった。 (B)では、Ca置換により、電気伝導が増大し、低温で強磁性が出現する(低濃度の場合はスピングラス)というSr置換と類似の物性を示すことが判明した。La^<3+>サイトへの2価イオン導入すると、格子体積には関係なくholeの導入によりIS状態が安定すること、Ca^<2+>導入の場合、Sr^<2+>の場合に比べてholeのmobilityが小さいこと、さらに両置換とも、臨界量以上の置換でFermi準位に状態密度の発生することが明らかになった。, 14038221
2002 - 2002 - 摩擦の物理
松川 宏; 鈴木 勝; 前田 京剛; 川端 和重; 那須野 悟; 三浦 浩治
日本学術振興会, 科学研究費助成事業, 大阪大学, 基盤研究(C), 内部に多くの自由度を持つ巨視的な系に外力を加えた場合、広義の摩擦を伴う複雑な運動を示すことがある。これに関した現象は固体界面の滑り摩擦から地震、電荷密度波、磁束格子など電子の巨視的凝縮相でのある種の秩序の運動など様々な分野の広いスケールに渡る。本研究では、研究代表者、分担者による周到な準備のもと、8月20〜22日に大阪大学豊中キャンパスにおいて、異なる分野、異なるスケールにわたる広義の摩擦現象に関する実験研究者と理論研究者が集まり、これらの現象を総合的に議論し分野間の交流を深める研究会"摩擦の物理"を開催した。80名ほどの参加者を得て、活発な議論が行われたた。これらの活動を通じて、"摩擦の物理"に関する研究グループが形成され、その後、数回の話しあいを経て、明確な将来の研究計画が立てられた。そして11月には科学研究費補助金特定領域研究"摩擦の物理"の申請へと結実した。この研究組織は総括班と7つの計画研究班からなり、以下のことを目的としている。 本研究は、現代物性科学・技術の成果をもとに新しい視点から、工学を含めた様々な分野における多様な系・レベルの摩擦機構の研究を有機的に繋げ、ミクロスケールからマクロスケールにわたる現象の階層性を正しく取り込み、摩擦の基礎的機構を統一的に解明する。摩擦の普遍性と個別性を明かにし、物理科学の新しい概念を生み出すとともに、その成果を踏まえた新たな摩擦制御技術の創生を目指す。, 13894010
2001 - 2001 - Slippage of Helium Films
SUZUKI Masaru
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, The University of Electro-Communications, Grant-in-Aid for Scientific Research (C), Friction is a common force, but is poorly understood from a microscopic point of view. Recently, experimental observations of atomic-scale friction were reported using newly developed techniques, e.g., the atomic force microscope(AFM), and the quartz-crystal microbalance(QCM). And the peculiar friction nature has been observed in an atomic scale. Recently, Krim and her colleagues measured the mechanical response of noble-gas films on a noble-metal substrate at 77K using the QCM technique. On the other hand, One may expect that since the attraction force of helium atom is so weak, physisorbed helium films slide easily on a substrate. Thus motivated, we investigated the slippage of both superfluid and nonsuperfluid helium films on a two-dimensional porous material, hectrite. In the present experiments, the ultrasonic technique was adopted for the measurements of the mechanical response of these films. When the film slips, a rapid increase in sound velocity and an attenuation peak are observed. We found that nonsuperfluid helium films slip from the oscillating substrate under certain conditions. Up to the coverage at which the fluid state appears at absolute zero, nonsuperfluid ^3He and ^4He films slipped from the oscillation at low temperatures, and this slippage was inhibited as the coverage increases further. In addition, it was found that from the temperature dependence of the slippage, a thermally activated process plays an important role in the frictional force of this system., 11640340
1999 - 2000 - Spin-State Transitions and Lattice Anomalies in oxides near the Mott transition boundary
ASAI Koichizo; KOBAYASHI Yoshihiko; SUZUKI Masaru; YAMADA Nobuyoshi; KOHN Kei-ichirou
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, The University of Electro-Communications, Grant-in-Aid for Scientific Research (C), The purpose of the present project is to investigate the spin-state transitions in oxides which locate near the metal-insulater (Mott) transition boundary. Not only the magnetic but also the electronic transport and the lattice properties have been investigated since the interactions among spin, charge, and the lattice play an important role in the "spin-state transition" in these oxides. The followings are clarified. 1. Nuclear magnetic relaxations of ィイD159ィエD1Co and μィイD1+ィエD1 in LaCoOィイD23ィエD2 and LaィイD20.9ィエD2SrィイD20.1ィエD2CoOィイD23ィエD2 The nuclear relaxation rates (TィイD21ィエD2ィイD1-1ィエD1 and TィイD22ィエD2ィイD1-1ィエD1) of ィイD159ィエD1Co measured by NMR for single crystalline LaCoOィイD23ィエD2 show a thermal-activation-type temperature dependence with an activation energy of 180 K. The relaxations are proved to be due to hyperfine interactions with interacting paramagnetic electrons in thermally populated magnetic Co ions. The activation energy agrees with the energy difference between the low-spin (LS ; S=0) and the intermediate-spin (IS ; S=1) states previously proposed in the "two-stage spin-transition" model. In contrast to ィイD159ィエD1Co, the relaxation rate of μィイD1+ィエD1 increases on lowering temperature below 100 K, meaning that the rate increases as the population of nonmagnetic LS Co ions increases. At present, we do not understand the mechanism. 2. Lattice anomalies associated with the spin-state transitions in LaCoOィイD23ィエD2 Elastic anomalous (lattice softenings) associated with the spin-state transitions are found near 100 K and 500 K by ultrasonic measurements. The results are interpreted based on the "two-stage spin-transition" model successfully. An increase of the absorption of the sound is observed around 100 K, which may suggest a short-range orbital order of IS state Co ions. 3. Magnetic and transport properties of LaCoィイD21-xィエD2NiィイD2xィエD2OィイD23ィエD2 (x < 0.1) Co atoms are in IS state down to the lowest temperature and their magnetic moments freeze into a spin-glass state. The resistivity below 400 K decreases by the substitution, although its temperature dependence remains to be an activation type. The Seebeck effect suggests that the carriers are positive polarons although the Hall coefficient is negative. The magnetic-electronic transition near 500 K survives in the substituted samples. 4. Resonance Photoemission Constant initial state (ClS) spectra as well as energy distribution curve (EDC) are measured for LaCoOィイD23ィエD2 and LaィイD20.9ィエD2SrィイD20.1ィエD2CoOィイD23ィエD2. The Co(3p->3d) resonance energy depends on the spin-state of Co ions. The temperature dependences of CIS and EDC are interpreted with the "two-stage spin-transition" model. 5. Crystal growth of LaSrCoOィイD24ィエD2 with the KィイD22ィエD2NiFィイD24ィエD2 structure Crystal growth of a single crystal of LaSrCoOィイD24ィエD2 using floating-zone lamp-image furnace is tested. However, Crystals sufficiently large for neutron scattering experiments have not been obtained., 10640336
1998 - 1999 - 低温域における^3He-^4He相分離界面の界面張力の精密測定
鈴木 勝
日本学術振興会, 科学研究費助成事業, 電気通信大学, 奨励研究(A), 液体ヘリウムの表面(界面)の研究は、他の液体とは異なり、表面特有の素励起の存在やバルクの素励起がどのように表面に影響を与えるか、という基本的な問題を提起して興味深い。本研究で取り上げる^3He-^4He相分離界面は、圧力を加えることで相分離した2相のバルクの性質を制御できるというユニークな特徴を持つ。 平成9年度は、まず圧力下で0.15Kまでの低温域の界面張力の測定を行い、界面張力の圧力依存性を明らかにした。解明張力は7気圧までの低圧域では圧力の増加とともに減少し、7気圧以上の高圧域では圧力にほぼ依存せず一定の値をしめす。界面張力と^3He準粒子の化学ポテンシャルの圧力依存性から、界面での^3He吸着量を求めることができる。解析の結果、7気圧までの低圧域では、界面張力の減少に対応し^3Heが界面から排除される負吸着が起こっており、その大きさは圧力の増加とともに減少するという知見が得られた。これは、定性的には^3Heと^4Heとの零点振動の大きさの違いにより説明されると考えている。これらの結果は論文として報告した。 平成10年度は、0.15K以下の低温域での界面張力の毛細管上昇法による測定システムの設計・作製を行った。はじめに。測定対象として液体^3Heの自由表面の表面張力を試みた。これまで液体^3Heの表面張力は150mK以下でほとんど温度に依存しないと報告されており、本研究でもほぼ同様な傾向が観測された。現在、界面張力の測定を行なっている。, 09740272
1997 - 1998 - レーザー場による光学応答の制御 団体系への拡張
白田 耕蔵; 桂川 眞幸; 鈴木 勝
日本学術振興会, 科学研究費助成事業, 電気通信大学, 重点領域研究, 平成8年度よりレーザー場による光学応答の制御の研究を高密度の凝縮系;個体系、へ拡張する試みを開始した。作業物質として固体水素を用いることにより、孤立原子・分子系の量子性と固体の高密度性を兼ね備えた状況が実現し、水素原子系で実証してきた量子干渉効果を用いる非線形光学の研究が従来の原理実証の限界を越えて発展できる見通しを得た。 強結合を達成するための要点は、2光子遷移のラビ周波数がその遷移の位相緩和速度を越えることであり、そのためには系の位相緩和速度が遅いことが本質的に重要である。本年度においては、固体水素の振動励起準位の位相緩和速度をポンプ・プローブ型のコヒーレント反ストークスラマン散乱法により測定した。2台のレーザーを用い、1台のレーザーで誘導ラマンを立ち上げ、コヒーレンスを発生させ、もう1方のレーザーとそのコヒーレンスのビ-ト光を反ストークス光として測定した。測定は、通常の位相整合条件を満たす反ストークス光(リング)及び強結合に基づく自動位相整合反ストークス光(スポット)について行った。リングとスポットによる緩和の振る舞いは大きく異なり、スポットによる信号は緩和速度(ラマンのスペクトル幅)にして3MHzFWHMであるのに対し、リングの信号は3MHzFWHMから70kHzFWHMへと大きな変化を示すものとなった。この解釈はいまだ確定していないが、弱結合から強結合へ相互作用が発展するに連れて、励起状態の分子数密度が上昇し、それにより励起状態間の相互作用により緩和速度も速くなることを反映しているものと思われる。今回の結果は固体水素の振動励起状態の緩和速度が固体としては異例に遅いことを示すものであり、固体水素の強結合非線形光学の可能性を示すものである。また、緩和速度が変化するという結果は強結合へのシステムの発展を定式化する上で極めて示唆的である。, 09210206
1997 - 1997 - Study on Spin-State Transitions in LaCoO_3
ASAI Kichizo; KOHN Kei-ichirou; KOBAYASHI Yoshihiko; SUZUKI Masaru; YAMADA Nobuyoshi
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, The University of Electro-Communications, Grant-in-Aid for Scientific Research (C), The purpose of the present project is to clarify the spin-states of Co ions and the nature of the transition between them in LaCoO_3. "Spin-state transition" in LaCoO_3 has been a controversial issue for a long time ; both of two broad magnetic anomalies, one near 100 K and a second near 500 K,have been interpreted by a common spin-state transition of Co trivalent ions from the low-spin to the high-spin state, and the interpretation is inconsistent as a whole. In this project, not only the magnetic but also the electronic transport and the lattice properties have been investigated since the interactions among spin, charge, and the lattice are crucial in the "Spin-state transition" in LaCoO_3 which locates near the Mott transiton boundary. The followings are clarified. 1. Two spin-state transitions in LaCoO_3 Anomalous lattice expansions and lattice softenings were observed near 100 K and 500 K by neutron-diffraction and ultrasonic measurements, respectively. These lattice anomalies and also the temperature dependence of the Co magnetic moments are successfully interpreted in a wide temperature range based on a model involving low-spin (LS ; S=O), intermediate-spin (IS ; S=1), and high-spin (HS ; S=2) states of Co atoms. The first spin transition, near 100K,is from LS to IS,and the second, near 500 K,is from IS to a mixed state of IS and HS.These studies reveal the volume dependence of the energy of each spin-state quantitatively, and also indicate the correlation between the large drop in resistivity and the collapse of the energy gap between IS and HS states in the 500 K transition. The proposed model successfully interprets the observed pressure dependence of the susceptibillity. We also point out that "the two spin-state transitions" is a unique feature of LaCoO_3 among RCoO_3 (R=rare earth element). 2. Magnetic and Transport properties of La_<1-X>Sr_XCoO_3 and LaCo_<1-X>Ni_XO_3 (X<0.1) In both systems, Co atoms are in IS state down to the lowest temperature and their magnetic moments freeze into a spin-glass state. The resistivity below 400 K decreases by the substitution, although its temperature dependence remains to be the activation type. The Seebeck effect suggests that the carriers dominating the transport are positive polarons in both systems. However, the Hall coefficient is positive in La_<1-X>Sr_XCoO_3 but negative in LaCo_<1-X>Ni_XO_3. The magnetic-electronic transition near 500 K survives in the substituted samples. This finding is consistent with the model described above for undoped LaCoO_3. 3.Phtoemission, NMR,and muSR studies of LaCoO_3 The temperature dependences of the photoemission spectra and the nuclear relaxation rates of ^<59>Co measured by NMR are interpreted consistently with the model described above. We found an increase of the relaxation rates of mu^+ on lowering temperature below 100 K.A more investigation is neccessary to understand the spin-state transition which mu^+ sees in LaCoO_3., 08640449
1996 - 1997 - 超流動転移点近傍における表面張力の異常に関する^3He不純物効果
鈴木 勝
日本学術振興会, 科学研究費助成事業, 電気通信大学, 奨励研究(A), 液体^4Heの超流動転移点近傍での表面張力の振る舞いは、超流動転移というバルクの性質の変化が表面にどのような影響を与えるか、という基本的な問題を提起して興味深い。さらに、液相一気相臨界点を異なり、転移点の高温測低温測ともに表面が存在するというユニークな特徴を持つ。本研究では、液体^4Heに不純物として^3Heを加え、転移点近傍の表面張力が定量的にどのように変化するかを測定することにより超流動転移と表面張力の関係を明らかにする。具体的には、1)表面張力の異常はBose凝縮体(または超流動密度)に結びつけられるかどうか。2)MikheevとFisherにより指摘された2mKの異常の不純物効果とそのメカニズムはなにか、について新しい知見を得ることを目的とする。 本研究では、実験の準備としてクライオスタットの改良および測定系の安定度を向上させる改良を行うと同時に、これまでに、予備的な実験として次のことを行った。 1)液体^4Heの表面張力の絶対値の測定:最近、フランスのグループは、薄膜の第3音波の測定より表面張力の絶対値がこれまでの値より6%ほど大きいと報告した。本実験では、試料液体の厚さの変化による表面張力の絶対値の系統誤差を評価したが系統誤差は見られず、これまで報告された絶対値に一致する結果を得た。2)小量の^3Heを不純物として混合したときの表面張力の測定:液体^4He試料に0.14%の^3He不純物を混合し、λ点近傍の表面張力の異常を測定した。予備的な測定があるが、純粋な^4Heとほぼ同様な振る舞いをすることが見いだされた。つまり、上記の2mKの異常は^3He不純物の濃度には依存しない。これは、この異常のメカニズムの解明に手がかりを与えるものと期待される。, 08740269
1996 - 1996 - レーザー場による光学応答の制御:固体系への拡張
白田 耕藏; 鈴木 勝
日本学術振興会, 科学研究費助成事業, 電気通信大学, 重点領域研究, 本研究の目的は、レーザー場による光学応答の制御の研究を気体原子系から高密度の固体系に拡張し、研究の新しいフェーズへの端緒を切り開くことを目指すものである。対象とする物質は量子固体として知られる固体水素である。 本計画は実験面で大きく二つに分けることができる。一つは固体水素単結晶の作製であり、他方は非線形光学実験である。前者については、加圧液相成長法を開発し良質の固体水素単結晶を製作する見通しを得た。本方法で得た固体水素の単結晶は4Kでもクラック無しに維持できる良質のものである。この結果は、「4Kで光学的に良質な固体水素単結晶は液相成長では生成不可能である」という常識を覆すものである。また、ここで得た結晶の光学的均一性は現在までベストの方法とされてきた気相成長法によるものを上回るものである。本法を更に発展させサブミクロンの薄膜からバルク単結晶まで種々の形態の良質の固体水素を準備できるよう研究を進展させつつある。 後者の非線形光学実験は誘導ラマン散乱の実験に集中した。その結果は極めて驚くべきものである。反ストークス光の発生過程についての位相整合条件は、非線形光学の誕生以来信じられてきたように「物質系の屈折率分散によって決定される」ものではなく、レーザー場と物質系が全体系としての固有状態を自己組織的に発展させることにより任意性をもって成り立ち得ることが実験的に示された。現在さらに、この現象を定量的に明らかにするため、バルク単結晶を用いたcw半導体レーザーによるストークス光の注入同期、薄膜サンプルと励起光・ストークス光として独立のレーザーを用いる実験を進展させつつある。今回示した結果は固体水素が本質的に持つ非線形光学媒質・レーザー媒質としての極めて優れたポテンシャルを証明するものであり、関連分野の世界で大きな注目を集めておりすでに4種の国際会議から招待講演の依頼を受けている。, 08224207
1996 - 1996 - Development of High Resolution Acoustic Microscope Using Superfluid ^4He
OKUDA Yuichi; KARAKI Koichi; SUZUKI Masaru
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Tokyo Institute of Technology, Faculty of Science, Grant-in-Aid for Developmental Scientific Research (B)., An acoustic microscope has been developed which makes use of pressurized superfluid helium as an acoustic coupling medium. By pressurizing superfluid ^4He, the efficiency of antireflection coating increases because of the increase of the acoustic impedance of the liquid ^4He, and the power level of saturation caused by nonlinearity of the superfluid ^4He is raised. A good signal-to-noise ratio of imaging is thus obtained even at 1.9K, relatively high temperature. And for the frequency 850MHz, under 13atm at 0.3K, the resolution of about 0.25mum was obtained by nonlinear effects. It exceeds the diffraction limit. We have measured the power dependence of the propagation of coherent focused acoustic pulse in superfluid ^4He underseveral pressures. At the low pressure region where the dispersion relation is anomalous, the simple saturation and the weak depletion were observed. On the other hand, at the higher pressure region where the dispersion relation becomes normal, the completely new nonlinear phenomena have been observed. That is, when the input power increases, the received power increases monotonously. Saturates and rapidly depletes. As the input power is increased further, the received power increases and depletes again. To explain this phenomenon, we propose a mixed nonlinear acoustic process, which consists of two different nonlinear processes. One is the 4-phonon decay process and the self-amplification of its decay products, and the other is the harmonic generation and its recovery to fundamental wave by the property of the focused beam. To verify this model. We have observed the second harmonics and shown that the second harmonics is generated in superfluid ^4He. Moreover, we have measured the resolution of acoustic microscope and observed its improvement beyond the diffraction limit at nonlinear region. Therefore, it shows that the fundamental wave recovered from harmonics exists in superfluid ^4He, too. This model for the nonlinear phenomena in pressurized superfluid ^4He is thus verified and the essential part of the phenomena is understood., 01840008
1989 - 1990