HAJIME　NISHIOKA

President and Members of the Board of DirectorsMember of the Board of Directors
  • Profile:
    エキシマレーザー、相対論的電子ビーム発生装置、紫外光学素子、ファラデー回転素子、紫外可飽和吸収体、色素レーザー、光音響法による微小非線形吸収計測、超短パルスレーザー、波長変換、過渡ラマンパルス圧縮、チタンサファイヤレーザー、非線形ビーム伝搬、超広帯域レーザー、周波数位相共役波発生、量子干渉による吸収放出制御、光学フォノン干渉
Researcher Information

Degree

  • 博士(工学）, 大阪大学

Research Keyword

  • optical coatings
  • nonlinear optics
  • optelectronics
  • lasers
  • 光学薄膜
  • 量子エレクトロニクス
  • 非線形光学
  • レーザー

Field Of Study

  • Nanotechnology/Materials, Applied physics - general
  • Nanotechnology/Materials, Optical engineering and photonics

Career

  • Apr. 2024 - Present
    The University of Electro-Communications, Menber of the Board of Direction, 理事（研究・産学官連携戦略担当）
  • 01 Apr. 2020 - 31 Mar. 2024
    電気通信大学, 情報理工学域, 学域長（併任）
  • Apr. 2023 - Mar. 2024
    電気通信大学 学術院, 学術院長（併任）
  • 01 Apr. 2021 - 31 Mar. 2022
    電気通信大学, 学術院, 学術院長（併任）
  • 01 Nov. 2014
    電気通信大学, レーザー新世代研究センター, 教授（兼務）
  • 01 Apr. 2014
    電気通信大学大学院, 情報理工学研究科, 教授
  • 01 Apr. 2007 - 31 Mar. 2014
    電気通信大学, レーザー新世代研究センター, 准教授
  • Apr. 2001 - Mar. 2002
    大阪大学, 大学院工学研究科, 助教授（併任）

Educational Background

  • Jun. 1985
    Osaka University, Graduate School, Division of Engineering, 電磁エネルギー工学専攻
  • Mar. 1985
    The University of Electro-Communications, Graduate School, Division of Electro Communications, 通信工学専攻
  • Mar. 1983
    The University of Electro-Communications, Faculty of Electro Communications, 通信工学科

Member History

  • 01 Jun. 2014 - 31 May 2016
    学会誌「レーザー研究」編集委員会 副委員長, レーザー学会, Society
  • 2005 - 2014
    レーザー研究 編集委員, レーザー学会, Society
  • Jan. 2007 - Feb. 2013
    超高速光エレクトロニクス研究専門委員会, 電子情報通信学会, Society, フェムト秒・アト秒基礎科学
  • Oct. 2006 - Sep. 2008
    光・量子発生・制御フロンティア技術調査専門委員会, 電気学会, Society
  • 1998 - 2008
    東京支部委員, レーザー学会, Society
  • 2004 - 2006
    次世代バイオメディカル・レーザ応用技術調査専門委員会, 電気学会, Society
  • 2004 - 2006
    光量子コヒーレンス制御技術調査専門委員会 委員長, 電気学会, Society
  • 2003 - 2006
    JJAP 編集委員, 応用物理学会, Society
  • 2002 - 2003
    レーザーハンドブック 編幹事, レーザー学会, Society
  • 1998 - 2000
    「光学」編集委員, 日本光学会, Society
Research Activity Information

Award

  • Apr. 2009
    The Japan society of Applied Physics
    APEX/JJAP Editorial Contribution Award
  • 1996
    研究表彰 光科学技術研究振興財団
  • 1992
    電気学会優秀論文発表賞

Paper

  • Generation of 300 nm bandwidth 0.5 mJ pulses near 1 μm in a single stage gas filled hollow core fiber
    Xiaoyang Guo; Shigeki Tokita; Kento Yoshii; Hajime Nishioka; Junji Kawanaka
    Optics Express, OSA - The Optical Society, 25, 18, 21171-21179, 04 Sep. 2017, Peer-reviwed, A simple and compact spectral-broadening system is presented that is based on a single-stage statically pressurized Ar filled core fiber. By optimizing the inner diameter of the core fiber, a bandwidth of 300 nm is obtained. This is the broadest bandwidth known to date with millijoule level energy near the 1-μm wavelength by a single stage filled core fiber.
    Scientific journal, English
    DOI URL
  • Hundred-picosecond narrowband chirped-pulse generation in an Yb:YAG regenerative amplifier using transmission gratings
    Sungln Hwang; Shigeki Tokita; Toshiyuki Kawashima; Hajime Nishioka; Junji Kawanaka
    JAPANESE JOURNAL OF APPLIED PHYSICS, IOP PUBLISHING LTD, 55, 12, 122702-1-122702-5, Dec. 2016, Peer-reviwed, We have demonstrated a seed source for an optical parametric chirped pulse amplification pumping source through a cryogenically cooled Yb:YAG regenerative amplifier, which can vary the pulse duration depending on the number of passes and generate a very high chirp rate. The Fourier-transform-limited pulse duration of 10 ps was extended to a few hundred picoseconds (109 to 165 ps) to prevent damage to the gain medium in the subsequent high-pulse-energy pumping source, which was seeded by the regenerative amplifier. This was achieved by inserting a transmission diffraction grating pair inside the cavity of the regenerative amplifier. The variable pulse duration could be set between 109 and 165 ps by electronically adjusting the pass number of pulses inside the cavity. The stretched pulse duration and the spectral width as functions of the pass number were characterized by considering the dispersion from the grating stretcher as well as the gain narrowing effect. (C) 2016 The Japan Society of Applied Physics
    Scientific journal, English
    DOI URL
  • Development of ultra-broadband frontend light source for OPCPA using partially-deuterated KDP crystals
    Kento Yoshii; Shigeki Tokita; Xiaoyang Guo; Koichi Iyama; Minoru Yoshida; Toshiyuki Kawashima; Hajime Nishioka; Junji Kawanaka
    May 2016, Peer-reviwed
    International conference proceedings, English
  • High power diode-pumped solid-state lasers by using cryogenic Yb:YAG composit ceramics
    Junji Kawanaka; Shigeki Tokita; Koichi Iyama; Toshiyuki Kawashima; Hajime Nishioka
    Mar. 2016, Peer-reviwed, Invited
    International conference proceedings, English
  • 1 J, 100 Hz, diode-pumped Yb:YAG ceramic laser for OPCPA pumping
    Junji Kawanaka; Shigeki Tokita; Koichi Iyama; Toshiyuki Kawashima; Hajime Nishioka
    Dec. 2015, Peer-reviwed, Invited
    International conference proceedings, English
  • Pulse stretching in a narrow-band Yb:YAG regenerative amplifier using transmission gratings
    Shigeki Tokita; SungIn Hwang; Toshiyuki Kawashima; Hajime Nishioka; Junji Kawanaka
    Proceedings of 2015 11th Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR), 4, DOI10.1109/CLEOPR.2015.7376128, 24 Aug. 2015
    International conference proceedings, English
  • Development of 1 J, 100 Hz Yb:YAG laser amplifier system for OPCPA pumping
    Shigeki Tokita; Martin Divoky; SungIn Hwang; Koichi Iyama; Toshiyuki Kawashima; Hajime Nishioka; Junji Kawanaka
    Proceedings of 2015 11th Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR), 4, DOI10.1109/CLEOPR.2015.7376127, 24 Aug. 2015
    International conference proceedings, English
  • 1 J, 100 Hz Multiple Active-Mirror Laser Amplifier Using YAG /Yb:YAG Composite Ceramics
    Shigeki Tokita; Martin Divoky; SungIn Hwang; Toshiyuki Kawashima; Hajime Nishioka; Antonio Lucianetti; Junji Kawanaka
    Apr. 2015, Peer-reviwed
    International conference proceedings, English
  • Pulse stretching in a cryogenic-Yb:YAG regenerative amplifier using transmission gratings
    Shigeki Tokita; SungIn Hwang; Toshiyuki Kawashima; Hajime Nishioka; Junji Kawanaka
    Apr. 2015, Peer-reviwed
    International conference proceedings, English
  • Stokes suppression and supercontinuum generation by differential two-phonon excitation
    Hajime Nishioka
    OPTICS EXPRESS, OPTICAL SOC AMER, 22, 22, 26457-26461, Nov. 2014, Peer-reviwed, Stimulated Raman scattering driven by differential coupling of two phonon modes has been demonstrated. These phonon modes are coherently and strongly coupled by external fields via two-phonon excitation at the first Brillouin zone boundary. Up to 11th order of sidebands and a supercontinuum covering entire visible region have been observed. The original Stokes and anti-Stokes lines by the single-phonon stimulated Raman scattering were significantly suppressed. (C) 2014 Optical Society of America
    Scientific journal, English
    DOI URL
  • Phase-locked Raman sidebands generated by two-phonon interference
    Hajime Nishioka
    Proceedings of the 3rd advanced lasers and photon sources, The Laser Society of Japan, 58-59, 22 Apr. 2014
    International conference proceedings, English
  • Coherent superposition of few-cycle laser pulses based on Frequency resolved two-wave-mixing
    Hajime Nishioka; Hiroka Nahara; Tsukasa Morishita
    The 2nd Advanced Lasers and Photon Sources (ALPS'13), Paper ALPS3-3, pp. 41-42, Apr. 2013
    International conference proceedings, English
  • Integrated Spectral Shearing Interferometer
    Hitoshi Tomita; Hajime Nishioka
    The 1st Advance Laser and Photon Sources(ALPS2012), ALPS1-5, Apr. 2012, Peer-reviwed
    International conference proceedings, English
  • Spectral shearing interferometer with frequency- and time-resolved sum-frequency mixing
    Hitoshi Tomita; Hajime Nishioka
    OPTICS EXPRESS, OPTICAL SOC AMER, 19, 18, 17173-17178, Aug. 2011, Peer-reviwed, A two-dimensional spectral-shearing interferogram has been acquired instantaneously by frequency-and time-resolved sum-frequency conversion where the phase-matching angle and transverse-delay of crossed-pump beams in a nonlinear crystal serve as frequency-time decomposed imaging. The two spectrally sheared components travel the same path after upconversion. A picoseconds delay-scanned interferogram is accumulated on a 2D image sensor. (C) 2011 Optical Society of America
    Scientific journal, English
    DOI URL
  • Broadband anti-Stokes generation in a CVD-grown single crystal diamond pumped by two chirped pulses
    Hajime Nishioka
    2011 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO), IEEE, CTuX4, 2011, Peer-reviwed, Broadband anti-Stokes emission having a bandwidth of 15,000 cm(-1) has been generated by non-collinear two chirped pump pulses. A low energy Stokes shift of 175 +/- 8 cm(-1) has been observed under the two-pulse excitation. (C) 2011 Optical Society of America
    International conference proceedings, English
  • Wide-time-range spectral-shearing interferometry
    Hitoshi Tomita; Hajime Nishioka
    OPTICS EXPRESS, OPTICAL SOC AMER, 17, 16, 14023-14028, Aug. 2009, Peer-reviwed, A long-time-range spectral-shearing interferometry has been demonstrated by frequency mixing with two-color monochromatic fields. Strongly chirped pulses with quadratic and cubic phase distortion have been characterized. A linearly chirped pulse having 2.2 ps (full duration of 6 ps) has been measured with a coaxial two-color field generated by a narrow-gap passive etalon. Substantial extensions in the time range can be expected with a highly coherent two-color source, i. e., frequency stabilized lasers, or two longitudinal modes in the frequency comb. (C) 2009 Optical Society of America
    Scientific journal, English
    DOI URL
  • Wide-range spectral shearing interferometry
    Hajime Nishioka; Hitoshi Tomita
    2009 CONFERENCE ON LASERS AND ELECTRO-OPTICS AND QUANTUM ELECTRONICS AND LASER SCIENCE CONFERENCE (CLEO/QELS 2009), VOLS 1-5, IEEE, 1662-1663, 2009, Peer-reviwed, A new scheme of spectral shearing interferometer providing a wide observation window has been demonstrated. Few-cycle pulse has been measured with a temporal observation/resolution ratio of >10(3) and a dynamic range of >10(8). (C) 2009 Optical Society of America
    International conference proceedings, English
  • Photorefractive Amplification of Few-cycle Laser Pulses
    Hajime NISHIOKA; Shuji OHTA; Hitoshi TOMITA
    The Review of Laser Engineering, supplemental, 1113-1114, Oct. 2008, Peer-reviwed
    Scientific journal, English
  • Bandwidth enhancement of optical parametric chirped pulse amplification by temporally delayed two pump beams
    Kanade Ogawa; Makoto Aoyama; Yutaka Akahane; Koichi Tsuji; Junji Kawanaka; Tetsuo Harimoto; Hajime Nishioka; Masayuki Fujita; Koichi Yamakawa
    JAPANESE JOURNAL OF APPLIED PHYSICS, JAPAN SOCIETY APPLIED PHYSICS, 47, 6, 4592-4594, Jun. 2008, Peer-reviwed, We have demonstrated ultra-broadband optical parametric chirped-pulse amplification of more than 350 nm bandwidth in the near-infrared region. We have observed a substantial enhancement (nearly 2-fold) of the parametric amplification bandwidth by using time-delayed two broadband pump pulses at degeneracy.
    Scientific journal, English
    DOI URL
  • Simple spectral-shearing interferometer for wide-temporal coverage
    Hitoshi Tomita; Hajime Nishioka
    The 6th Asia Pacific Laser Symposium, 142, Jan. 2008
    International conference proceedings, English
  • Photorefractive amplification of few-cycle laser pulses
    Hajime Nishioka; Shuji Ohta; Hitoshi Tomita
    The 6th Asia Pacific Laser Symposium, 84, Jan. 2008
    International conference proceedings, English
  • High-energy, diode-pumped, cryogenically-cooled Yb:LiYF4 chirped-pulse amplification system
    M. Aoyama; K. Ogawa; Y. Akahane; K. Tsuji; A. Sugiyama; J. Kawanaka; H. Nishioka; M. Fujita; K. Yamakawa
    2008 CONFERENCE ON LASERS AND ELECTRO-OPTICS & QUANTUM ELECTRONICS AND LASER SCIENCE CONFERENCE, VOLS 1-9, IEEE, 2525-+, 2008, We present a cryogenically-cooled Yb:LiYF4 chirped-pulse amplification system with an energy of >100-mJ boosted by regenerative and multi-pass amplifiers for pumping multi-terawatt, few-cycle optical parametric chirped-pulse amplification. (C)2008 Optical Society of America.
    International conference proceedings, English
  • High-resolution spectral-shearing interferometry
    Hitoshi Tomita; Hajime Nishioka
    Conference Proceedings - Lasers and Electro-Optics Society Annual Meeting-LEOS, 701-702, 2008, We present spectral-shearing interferometry with a high group-delay resolution that is defined as a ratio of the maximum temporal window and the shortest pulse duration. This technique allows the resolution of 104. ©2008 IEEE.
    International conference proceedings, English
    DOI URL
  • Bandwidth enhancement of optical parametric chirped-pulse amplification by temporally delayed twin pump beams
    K. Yamakawa; M. Aoyama; Y. Akahane; K. Tsuji; K. Ogawa; T. Harimoto; J. Kawanaka; H. Nishioka; M. Fujita
    Conference Proceedings - Lasers and Electro-Optics Society Annual Meeting-LEOS, 779-780, 2008, We have demonstrated ultra-broadband optical parametric chirped-pulse amplification of more than 550-nm bandwidth by using time-delayed two broadband pump pulses at degeneracy. ©2008 IEEE.
    International conference proceedings, English
    DOI URL
  • 励起光の発散角を利用した超広帯域光パラメトリック・チャープパルス増幅法
    小川 奏; 赤羽 温; 張本鉄雄; 青山 誠; 辻 公一; 河仲準二; 西岡 一; 藤田雅之; 山川考一
    レーザー研究, The Laser Society of Japan, 35, 9, 596-598, Sep. 2007, Peer-reviwed, We demonstrated ultra-broadband optical parametric chirped-pulse amplification using a picosecond diverging pump beam in the 1 μm wavelength region. An amplification bandwidth of more than 400 nm was achieved in a type-I BBO crystal with a gain of 1.2×105.
    Scientific journal, Japanese
    URL
    URL 2
    DOI URL
  • High-energy, diode-pumped, picosecond Yb : YAG chirped-pulse regenerative amplifier for pumping optical parametric chirped-pulse amplification
    Y. Akahane; M. Aoyama; K. Ogawa; K. Tsuji; S. Tokita; J. Kawanaka; H. Nishioka; K. Yamakawa
    OPTICS LETTERS, OPTICAL SOC AMER, 32, 13, 1899-1901, Jul. 2007, Peer-reviwed, A diode-pumped, cryogenic-cooled Yb:YAG regenerative amplifier utilizing gain-narrowing has been developed. A 1.2-ns chirped-seed pulse was simultaneously amplified and compressed in the regenerative amplifier, which generated a 35-ps pulse with similar to 8-mJ of energy without a pulse compressor. Second-harmonies of the amplified pulse was used to pump picosecond two-color optical parametric amplification. (c) 2007 Optical Society of America.
    Scientific journal, English
    DOI URL
  • Degenerate optical parametric chirped-pulse amplification with a spectral range over 200 nm using an Yb: YLF chirped-pulse amplification pump laser
    M. Aoyama; Y. Akahane; K. Ogawa; K. Tsuji; A. Sugiyama; T. Harimoto; J. Kawanaka; H. Nishioka; M. Fujita; K. Yamakawa
    The review of laser engineering, Jun. 2007
    Scientific journal, English
  • Degenerate Optical Parametric Chirped-Pulse Amplifier Pumped by an Yb:YLF Chirped-Pulse Ampfication Laser
    M. Aoyama; Y. Akahane; K. Ogawa; K. Tsuji; A. Sugiyama; T. Harimoto; J. Kawanaka; H. Nishioka; M. Fujita; K. Yamakawa
    The Review of Laser Engineering, Laser Society of Japan, 35, 6, 398-399, Jun. 2007, Peer-reviwed
    Scientific journal, English
    DOI URL
  • Ultra-broadband optical parametric chirped-pulse amplification using an Yb : LiYF4 chirped-pulse amplification pump laser
    K. Yamakawa; M. Aoyama; Y. Akahane; K. Ogawa; K. Tsuji; A. Sugiyama; T. Harimoto; J. Kawanaka; H. Nishioka; M. Fujita
    OPTICS EXPRESS, OPTICAL SOC AMER, 15, 8, 5018-5023, Apr. 2007, Peer-reviwed, We demonstrate ultra-broadband optical parametric chirped-pulse amplification of 300-nm bandwidth pumped by a broadband pulse delivered from a diode-pumped, cryogenically-cooled Yb:YLF chirpedpulse amplification laser. (c) 2007 Optical Society of America.
    Scientific journal, English
    DOI URL
  • Femtosecond pulse amplification by a two-photon arranged photorefractive amplifier
    Hajime Nishioka; Keisuke Hayasaka; Shuji Ohta; Hitoshi Tomita; Ken-ichi Ueda
    OPTICS EXPRESS, OPTICAL SOC AMER, 15, 8, 4830-4834, Apr. 2007, Peer-reviwed, Femtosecond pulse amplification by a two-photon arranged photorefractive amplifier ( TAPA) has been demonstrated. A gain bandwidth of 32 THz has been achieved with an extraction efficiency of 27%. (c) 2007 Optical Society of America
    Scientific journal, English
    DOI URL
  • “Intense few-cycle optical parametric chirped-pulse amplifier pumped by a cryogenically-cooled Yb-doped solid-state chirped-pulse amplification laser
    K. Ogawa; M.Aoyama; Y. Akahane; K. Tsuji; J. Kawanaka; H. Nishioka; T. Harimoto; M. Fujita; K. Yamakawa
    Jan. 2007
    Research society, English
  • 42-mJ Q-switched Active-Mirror Laser Oscillator with a Cryogenic Yb:YAG Ceramics
    J. Kawanaka; S. Tokita; H. Nishioka; K. Ueda; M. Fujita; T. Kawashima; H. Yagi; T. Yanagitani
    Advanced Solid-State Photonics, Jan. 2007
    Research society, English
  • All-optical dynamic chirp compensation of few-cycle optical pulses by frequency-domain phase conjugator
    Hajime Nishioka; Keisuke Hayasaka; Syuji Ohta; Hitoshi Tomita; Ken-ichi Ueda
    2007 CONFERENCE ON LASERS & ELECTRO-OPTICS/QUANTUM ELECTRONICS AND LASER SCIENCE CONFERENCE (CLEO/QELS 2007), VOLS 1-5, IEEE, 809-810, 2007, Peer-reviwed, All-optical phase-correction of few-cycle optical pulse has been demonstrated by a frequency-domain phase conjugator (FDPC). Temporally varying group-delay-dispersion is dynamically compensated by two-photon formed gratings in a highly transparent photo-refractive material. (C) 2007 Optical Society of America
    International conference proceedings, English
  • High-energy, diode-pumped, picosecond Yb:YAG chirped-pulse regenerative amplifier as a pump source for optical parametric chirped-pulse amplification
    Y. Akahane; M. Aoyama; K. Ogawa; K. Tsuji; K. Yamakawa; S. Tokita; J. Kawanaka; H. Nishioka
    2007 CONFERENCE ON LASERS & ELECTRO-OPTICS/QUANTUM ELECTRONICS AND LASER SCIENCE CONFERENCE (CLEO/QELS 2007), VOLS 1-5, IEEE, 915-+, 2007, Peer-reviwed, A diode-pumped Yb:YAG regenerative amplifier utilizing gain-narrowing has been developed. A chirped-seed pulse was amplified and compressed in the regenerative amplifier, simultaneously, which generated the picosecond pulses with similar to 8-mJ of energy without a pulse compressor. (C) 2007 Optical Society of America
    International conference proceedings, English
  • Multi-millijoule, diode-pumped, chirped-pulse Yb:KY(WO4)(2) regenerative amplifier
    K. Ogawa; Y. Akahane; M. Aoyama; K. Tsuji; K. Yamakawa; S. Tokita; J. Kawanaka; H. Nishioka
    2007 CONFERENCE ON LASERS & ELECTRO-OPTICS/QUANTUM ELECTRONICS AND LASER SCIENCE CONFERENCE (CLEO/QELS 2007), VOLS 1-5, IEEE, 917-+, 2007, Peer-reviwed, A diode-pumped, cryogenically-cooled Yb: KYW regenerative amplifier utilizing regenerative pulse shaping has been developed. An amplified pulse with an energy of 5.5 mJ and a broad bandwidth of 3.4 nm is achieved. (C) 2005 Optical Society of America
    International conference proceedings, English
  • Few-cycle terawatt optical parametric chirped-pulse amplification system using an Yb:YLF chirped-pulse amplification pump laser
    M. Aoyama; Y. Akahane; K. Ogawa; K. Tsuji; A. Sugiyama; K. Yamakawa; T. Harimoto; J. Kawanaka; H. Nishioka; M. Fujita
    2007 CONFERENCE ON LASERS & ELECTRO-OPTICS/QUANTUM ELECTRONICS AND LASER SCIENCE CONFERENCE (CLEO/QELS 2007), VOLS 1-5, IEEE, 2398-+, 2007, Peer-reviwed, We present an ultra-broadband optical parametric chirped-pulse amplification system with a 400 nm bandwidth pumped by two broadband pulses delivered from a liquid nitrogen cooled Yb:YLF chirped-pulse amplification laser. (C)2007 Optical Society of America
    International conference proceedings, English
  • Frequency-domain phase conjugator for a few-cycle and a few-nJ optical pulses
    Hajime Nishioka; Keisuke Hayakawa; Hitoshi Tomita; Ken-ichi Ueda
    ULTRAFAST OPTICS V, SPRINGER, 132, 119-+, 2007
    International conference proceedings, English
  • Multi-millijoule, diode-pumped, chirped-pulse Yb:KY(WO4) 2 regenerative amplifier
    K. Ogawa; Y. Akahane; M. Aoyama; K. Tsuji; K. Yamakawa; S. Tokita; J. Kawanaka; H. Nishioka
    Conference on Lasers and Electro-Optics, 2007, CLEO 2007, 15, 14, 8598-8602, 2007, Peer-reviwed, A diode-pumped, cryogenically-cooled Yb: KYW regenerative amplifier utilizing regenerative pulse shaping has been developed. An amplified pulse with an energy of 5.5 mJ and a broad bandwidth of 3.4 nm is achieved. © 2005 Optical Society of America.
    International conference proceedings, English
    DOI URL
  • Ultra-broadband optical parametric chirped-pulse amplification using a cryogenic-cooled Yb : YLF chirped-pulse amplification pump laser
    K. Yamakawa; M. Aoyama; Y. Akahane; K. Tsuji; K. Ogawa; T. Harimoto; J. Kawanaka; H. Nishioka; M. Fujita
    2007 IEEE LEOS ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS 1 AND 2, IEEE, 368-+, 2007, We have demonstrated ultra-broadband optical parametric chirped-pulse amplification of 300-nm bandwidth pumped by a diode-pumped, cryogenic-cooled Yb:YLF chirped-pulse amplification laser.
    International conference proceedings, English
  • Wide temporal coverage spectral shearing interferometer with a dual frequency mixer
    Hitoshi Tomita; Hajime Nishioka
    2007 IEEE LEOS ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS 1 AND 2, IEEE, 842-843, 2007, We have proposed a replica-free spectral shearing interferometer with a dual frequency local oscillator that warrants fixed frequency shift and wide temporal coverage. We applied this technique to characterize few-cycle and several-ps optical pulses.
    International conference proceedings, English
  • Automatic GDD compensation and amplification of few-cycle pulses by two-photon arranged diffractive optics
    Hajime Nishioka
    2007 IEEE LEOS ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS 1 AND 2, IEEE, 366-367, 2007, All-optical group-delay-dispersion compensation of few-cycle optical pulse has been demonstrated by a two-photon gated photosensitive Bragg grating. Ferntosecond pulse amplification based on coherent beam combing was presented.
    International conference proceedings, English
  • Development of High-Intensity Few-Cycle Optical Parametric Chirped-Pulse Amplifiers Pumped by an Yb:YLF Chirped-Pulse Amplification Laser
    M. Aoyama; Y. Akahane; K. Tsuji; K. Ogawa; J. Kawanaka; H. Nishioka; M. Fujita; K. Yamakawa
    LEOS 06, 47, Oct. 2006, Peer-reviwed
    International conference proceedings, English
  • All-optical temporal phase correction scheme for few-cycle optical pulses using diffractive optics
    Hajime Nishioka; Hitoshi Tomita; Keisuke Hayasaka; Ken-Ichi Ueda
    OPTICS EXPRESS, OPTICAL SOC AMER, 14, 16, 7447-7455, Aug. 2006, Peer-reviwed, All-optical phase correction scheme for few-cycle optical pulses has been proposed. The temporal phase structure of a phase-modulated pulse is recorded as spatial index modulation in a two-photon recording medium. This scheme drastically relaxes complicacy in stretcher design for few-cycle chirped pulse amplification (CPA) systems. (c) 2006 Optical Society of America.
    Scientific journal, English
  • Efficient Active-Mirror Laser Oscillator with a Cooled Yb:YAG Ceramics
    Junji Kawanaka; Shigeki Tokita; Hajime Nishioka; Ken-ichi Ueda; Masayuki Fujita; Toshiyuki Kawashima
    Advanced Solid-State Photonics, Feb. 2006
    Research society, English
  • Development of high-intensity few-eycle optical parametric chirped-pulse amplifiers pumped by an Yb : YLF chirped-pulse amplification laser
    M. Aoyama; Y. Akahane; K. Tsuji; K. Ogawa; T. Harimoto; J. Kawanaka; H. Nishioka; M. Fujita; K. Yamakawa
    2006 IEEE LEOS ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS 1 AND 2, IEEE, 540-+, 2006, Peer-reviwed, We present a few-cycle terawatt OPCPA system with a ultra-broad bandwidth of over 400 nm pumped by double broadband pulses delivered from a Yb:YLF CPA laser cooled to liquid nitrogen temperatures.
    International conference proceedings, English
  • Automatic compensation of higher order dispersion in chirped pulse amplification system by a nonlinear-recorded diffractive optics
    Hitoshi Tomita; Keisuke Hayasaka; Hajime Nishioka; Ken-Ichi Ueda
    Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference, CLEO/QELS 2006, CThEE5, 2006, Peer-reviwed, All-optical phase-correction scheme in a 10 fs CPA system using a frequency-domain phase conjugator (FDPC) has been proposed. The cubic and quadratic phase distortions are automatically eliminated by an optically programmable pre-compensator. © 2006 Optical Society of America.
    International conference proceedings, English
    DOI URL
  • 30-W, 7.5-mJ, Q-switched diode-pumped laser oscillator with a cooled Yb:YAG ceramics active mirror
    Junji Kawanaka; Shigeki Tokita; Hajime Nishioka; Ken-Ichi Ueda; Masayuki Fujita; Toshiyuki Kawashima; Hideki Yagi; Takaglmi Yanagitani
    Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference, CLEO/QELS 2006, CTuEE5, 2006, Peer-reviwed, A diode-pumped Q-switched laser oscillator with a liquid-nitrogen-cooled Yb:YAG ceramics active mirror has been demonstrated. 7.5-mJ pulse energy and 30-W average power were obtained. The maximum optical and slope efficiency were 62% and 71%, respectively. © 2005 Optical Society of America.
    International conference proceedings, English
    DOI URL
  • Automatic compensation of higher order dispersion in chirped pulse amplification system by a nonlinear-recorded diffractive optics
    Hitoshi Tomita; Keisuke Hayasaka; Hajime Nishioka; Ken-Ichi Ueda
    Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference, CLEO/QELS 2006, TOM2, 64, 2006, Peer-reviwed, All-optical phase-correction scheme in a 10 fs CPA system using a frequency-domain phase conjugator (FDPC) has been proposed. The cubic and quadratic phase distortions are automatically eliminated by an optically programmable pre-compensator. © 2006 Optical Society of America.
    International conference proceedings, English
    DOI URL
  • Dramatically improved laser characteristics of diode-pumped Yb-doped materials at low temperature
    J Kawanaka; S Tokita; H Nishioka; M Fujita; K Yamakawa; K Ueda; Y Izawa
    LASER PHYSICS, INTERPERIODICA, 15, 9, 1306-1312, Sep. 2005, Peer-reviwed, Dramatic improvements in the laser characteristics of ytterbium-doped materials were experimentally shown by cooling an ytterbium-doped laser crystal at low temperature. Quantum-defect-limited operation has been demonstrated in a diode-pumped free-running oscillator with a cooled Yb:YAG. The highest slope efficiency of 90% was obtained at a crystal temperature below 70 K, which was close to the theoretical Stokes efficiency of 91.2%. The optical-to-optical efficiency and laser gain were 74% and 8 cm(-1), respectively, at a low pump intensity of 1.3 kW/cm(2). By using an Yb:YLF crystal at 77 K, a 60-mJ diode-pumped chirped-pulse regenerative amplifier has been demonstrated. After temporal compression by using a parallel grating pair, 36-mJ, 795-fs pulses were generated at a 20-Hz repetition rate.
    Scientific journal, English
  • Diode-pumped Yb : YLF chirped-pulse regenerative amplifier for high average power operation
    J Kawanaka; H Nishioka; K Yamakawa; K Ueda
    XV International Symposium on Gas Flow, Chemical Lasers, and High-Power Lasers Pt 1 and 2, SPIE-INT SOC OPTICAL ENGINEERING, 5777, 358-360, 2005, Peer-reviwed, 60 mJ chirped-pulse power was obtained using a diode-pumped regenerative amplifier with a cooled Yb:YLF crystal at 20 Hz repetition rate. After temporal compression, 36 mJ, 795 fs pulses were generated. Our numerical calculation shows that 100 mJ output power at 1 kHz would be obtained by using a sapphire-sandwiched laser material and a 2-pass amplification scheme in regenerative cavity.
    International conference proceedings, English
    DOI URL
  • Two-photon gated femtosecond pulse recoding and regeneration in a single-chip diffractive optics
    Hajime Nishioka; Hitoshi Tomita; Keisuke Hayasaka; Ken-Ichi Ueda
    Conference on Lasers and Electro-Optics Europe - Technical Digest, CC4-4-FRI, 2005, Peer-reviwed
    International conference proceedings, English
    DOI URL
  • Active-mirror oscillator with cryogenically cooled Yb-doped materials
    Junji Kawanaka; Yasukazu Izawa; Hajime Nishioka; Ken-Ichi Ueda
    Conference on Lasers and Electro-Optics Europe - Technical Digest, CA2-3-MON, 2005, Peer-reviwed, A free-running oscillator by using an active mirror with a cryogenically cooled Yb:YLF has been demonstrated. Output energy and optical efficiency were 40mJ and 24%, respectively, in quasi continuous wave operation at 10Hz. © 2005 IEEE.
    International conference proceedings, English
    DOI URL
  • Instantaneous optical-phase-recording in a two-photon gated Bragg grating
    K Hayasaka; H Nishoka; K Ueda
    2005 PACIFIC RIM CONFERENCE ON LASERS AND ELECTRO-OPTICS, IEEE, 963-964, 2005, Peer-reviwed, Temporal phase structure of an optical pulse has been recoded with a 10 fs temporal resolution in a two-photon formed Bragg grating. The refractive index modulation of 0.01 has been achieved with 6 nano-joule IR laser pulses.
    International conference proceedings, English
  • Cryogenically-cooled active-mirror oscillator with Yb-doped material for inertial fusion energy driver
    J Kawanaka; S Tokita; H Nishioka; M Fujita; T Kawashima; T Yanagitani; K Ueda; Y Izawa
    2005 PACIFIC RIM CONFERENCE ON LASERS AND ELECTRO-OPTICS, IEEE, 83-84, 2005, Peer-reviwed, An active-mirror oscillator with a cryogenically cooled Yb:YLF has been demonstrated for the first time. Output pulse energy was 40mJ and 3.4mJ for the free-running and Q-switching modes, respectively, in quasi-cw pump at 10Hz.
    International conference proceedings, English
  • Frequency-domain phase conjugator by a two-photon gated Bragg grating for nJ laser pulses
    H Nishoka; K Hayasaka; H Tomita; K Ueda
    2005 IEEE LEOS Annual Meeting Conference Proceedings (LEOS), IEEE, 696-697, 2005, Temporal phase structure of a 10 fs optical pulse has been regenerated by a two-photon gated photosensitive Bragg grating. The refractive index modulation of Delta n=0.03 has been achieved with 6 nano-joule IR laser pulses.
    International conference proceedings, English
  • Femtosecond pulse recoding and regeneration by a two-photon gated periodic diffractive optics
    H Nishioka; H Tomita; K Ueda
    ULTRAFAST PHENOMENA XIV, SPRINGER-VERLAG BERLIN, 79, 777-779, 2005, A new scheme for pulse recording, time-reversed playback, and self-phase regeneration in a nonlinear diffractive device was proposed. The pulse regeneration has been demonstrated in a two-photon absorbing glass-chip. Numerical calculation shows that sufficient visibility in two-photon interference is possible for 100 times pulse compression.
    International conference proceedings, English
  • Femtosecond pulse encoding and self phase-reconstruction by Time-Ordered Recording/Readout in a Periodic Diffractive Optics (TORPEDO)
    Hajime Nishioka; Ken-ichi Ueda
    Conference on Lasers and Electro Optics, CFC-6, May 2004, Peer-reviwed
    International conference proceedings, English
  • Milli-joule operation of diode-pumped Yb:LiYF4 chirped-pulse regenerative amplifier for kilo-Heltz repetition rate
    J. Kawanaka; H. Nishioka; K. Ueda
    Conference on Lasers and Electro Optics, ITuI12, May 2004, Peer-reviwed
    International conference proceedings, English
  • Femtosecond pulse encoding and self phase-reconstruction by a two-photon-recorded single-tip diffractive optics
    Hajime Nishioka; Ken-ichi Ueda
    Advanced Solid-State Photonics, WC5, Feb. 2004, Peer-reviwed
    International conference proceedings, English
  • Diode-pumped Yb:LiYF4 chirped-pulse regenerative amplifier for high average power operation
    Junji Kawanaka; Koichi Yamakawa; Hajime Nishioka; Ken-ichi Ueda
    Advanced Solid-State Photonics, Optical Society of America, MC5, Feb. 2004, Peer-reviwed
    International conference proceedings, English
  • Femtosecond pulse recoding and self-regeneration in a two-photon gated periodic diffractive optics
    H Nishioka; H Tomita; K Ueda
    2004 IEEE LEOS ANNUAL MEETING CONFERENCE PROCEEDINGS, VOLS 1 AND 2, IEEE, 595-596, 2004, A new scheme for pulse recording, time-reversed playback, and self-regeneration in a diffractive device was proposed. Sclf-pulse-regeneration in a two-photon-recorded glass tip has been demonstrated.
    International conference proceedings, English
  • 30-mJ, diode-pumped, chirped-pulse Yb : YLF regenerative amplifier
    J Kawanaka; K Yamakawa; H Nishioka; K Ueda
    OPTICS LETTERS, OPTICAL SOC AMER, 28, 21, 2121-2123, Nov. 2003, Peer-reviwed, A diode-pumped chirped-pulse regenerative amplifier with a cooled Yb:YLF crystal has been developed. The output pulse energy is 30 mJ at 20-Hz repetition rate. A high effective extraction efficiency of 68% is obtained, which is attributed to reduced saturation fluence at low temperature and to a high effective pulse energy fluence during regenerative amplification. After pulse compression by use of a parallel grating pair, 18-mJ pulse energy and 795-fs pulse duration are obtained. (C) 2003 Optical Society of America.
    Scientific journal, English
  • Super-broadband continuum generation with transient self-focusing of a TW laser pulse in rare gases
    H. Nishioka; K. Ueda
    Appl. Phys. B, 77, 2-3, 171-175, Jul. 2003, Peer-reviwed
    Scientific journal, English
  • Multi-ten-milli-joule operation of diode-pumped Yb:LiYF4 chirped-pulse regenerative amplifier
    J. Kawanaka; K. Yamakawa; H. Nishioka; K. Ueda
    Conference on Lasers and Electro-Optics (CLEO), CWA35, May 2003, Peer-reviwed
    International conference proceedings, English
  • 20-mJ diode-pumped chirped-pulse regenerative amplifier with a cooled Yb:LiYF4
    Junji Kawanaka; Hajime Nishioka; Koichi Yamakawa; K. Ueda
    Proceedings of SPIE - The International Society for Optical Engineering, 5120, 287-290, 2003, A 24-mJ diode-pumped chirped-pulse regenerative amplifier with a cooled Yb:LiYP4 crystal has been developed. A 10-mJ pulse energy with sub-ps pulse duration was obtained with a 660 fs pulse duration after compression.
    International conference proceedings, English
  • Spectral control of diode-pumped Yb:LiYF4 chirped-pulse regenerative amplifier
    Junji Kawanaka; Koichi Yamakawa; Hajime Nishioka; Ken-Ichi Ueda
    Conference on Lasers and Electro-Optics Europe - Technical Digest, 451, 2003, Peer-reviwed, Yb:LiYF4 (Yb:YLF) crystal is focused on as one of the promised laser materials in the diode-pumped ultrahigh-peak-power lasers due to its high energy storage, wide spectral emission range, low nonlinear refractive index and high thermal conductivity. In this paper, spectral control with a pellicle was demonstrated for broadening a spectral width of the regenerative amplified pulse. Sub-100 fs pulse duration with over-ten-milli-joule pulse energy after compression could be obtained with pellicle spectral shaping and additional pump diode by replacing the fiber stretcher to an antiparallel grating pair pulse stretcher. © 2003 IEEE.
    International conference proceedings, English
    DOI URL
  • 全光領域コヒーレント過渡現象の研究
    西岡 一
    文部科学省科学研究費補助金、基盤研究(B)報告書, -, Oct. 2002
    Research society, Japanese
  • Absorption and emission control in a femtosecond-dephasing medium by an intense hypercontinuum
    Hajime Nishioka; Ken-ichi Ueda
    JST international symposium on Control of molecules in intense laser fields, Paper P-65, Sep. 2002
    International conference proceedings, English
  • Frequency-domain phase-conjugate femtosecond pulse generation using frequency resolved cross-phase modulation
    H Nishioka; S Ichihashi; K Ueda
    OPTICS EXPRESS, OPTICAL SOC AMER, 10, 18, 920-926, Sep. 2002, Peer-reviwed, Schemes to generate a frequency-domain phase-conjugate pulse by frequency mixing prechirped pulses are proposed. A femtosecond time-reversed replica is generated by the temporal-frequency-converted optical parametric processes. (C) 2002 Optical Society of America.
    Scientific journal, English
    DOI URL
  • Improved high-field laser characteristics of a diode-pumped Yb : LiYF4 crystal at low temperature
    J Kawanaka; K Yamakawa; H Nishioka; K Ueda
    OPTICS EXPRESS, OPTICAL SOC AMER, 10, 10, 455-460, May 2002, Peer-reviwed, We have demonstrated a diode-pumped Yb:LiYF4 laser oscillator at liquid nitrogen temperature in free-running mode. The obtained laser gain was 21 cm(-1),which was 15 times as high as that at room temperature. The effective tuning range was broadened to 35 nm due to absorption spectral narrowing. (C) 2002 Optical Society of America.
    Scientific journal, English
    DOI URL
  • 24-mJ, diode-pumped, chirped-pulse regenerative amplifier with a cooled Yb:LiYF4
    J. Kawanaka; K. Yamakawa; H. Nishioka; K. Ueda
    Post deadline paper of Conference on Lasers and Electro-optics (CLEO'02), CPDC8, May 2002, Peer-reviwed
    International conference proceedings, English
  • Q-switching operation with a diode-pumped cooled Yb:LiYF4 for chirped pulse regenerative amplifier
    J. Kawanaka; H. Nishioka; K. Yamakawa; K. Ueda
    Technical Digest of Conference on Lasers and Electro-Optics (CLEO'02), 404, May 2002, Peer-reviwed
    International conference proceedings, English
  • Diode-pumped Q-switched Yb : LiYF4 laser at low temperature for chirped pulse regenerative amplification
    J Kawanaka; K Yamakawa; H Nishioka; K Ueda
    ADVANCED SOLID-STATE LASERS, PROCEEDINGS, OPTICAL SOC AMERICA, 68, 397-400, 2002, Peer-reviwed, A diode-pumped regenerative amplifier with a cooled Yb:LiYF4 crystal has been constructed for chirped pulse amplification. The output energy of 4.5 mJ in a Q-switching operation mode was observed. The small signal gain and cavity loss were estimated to calculate an output energy of 12 mJ in regenerative amplification of a chirped seed pulse. (C) 2001 Optical Society of America.
    International conference proceedings, English
  • Frequency-domain phase-conjugate femtosecond pulse generation using frequency resolved cross-phase modulation
    H. Nishioka; S. Ichihashi; K. Ueda
    Optics Express, Optical Society of America (OSA), 10, 18, 920-926, 2002, Peer-reviwed, Schemes to generate a frequency-domain phase-conjugate pulse by frequency mixing prechirped pulses are proposed. A femtosecond time-reversed replica is generated by the temporal-frequency-converted optical parametric processes. © 2002 Optical Society of America.
    Scientific journal, English
    DOI URL
  • Efficient femto-second laser operation with LD-pumped Yb-doped materials at low temperature
    J. Kawanaka; H. Nishioka; K. Yamakawa; K. Ueda
    2001 International Laser Lightwave and Microwave Conference Proceedings (NNSFC/OSA/LSJ/STCSM/IEEE), 24-27, Nov. 2001
    International conference proceedings, English
  • An efficient laser oscillator with a wide tuning range using Yb-doped materials at low temperature
    J. Kawanaka; K. Yamakawa; H. Nishioka; K. Ueda
    Proceedings of the second symposium on advanced photon research (JAERI-Conf 2001-011), 82-83, Oct. 2001
    International conference proceedings, Japanese
  • Tunable continuous-wave Yb : YLF laser operation with a diode-pumped chirped-pulse amplification system
    J Kawanaka; H Nishioka; N Inoue; K Ueda
    APPLIED OPTICS, OPTICAL SOC AMER, 40, 21, 3542-3546, Jul. 2001, Peer-reviwed, We have demonstrated a diode-pumped Yb:LiYF4 (Yb:YLF) laser oscillator for the first time to our knowledge. A wide tuning range of 25 nm and a high slope efficiency of 50% were obtained at a high laser-diode pump intensity of 100 kW/cm(2). Emission and absorption spectra of the Yb:YLF crystal at 8 K represent a wide laser gain width of 38 nm, indicating efficient laser operation similar to that of a four-level laser system with a reduced saturation fluence of 11 J/cm(2). (C) 2001 Optical Society of America.
    Scientific journal, English
  • Absorption and emission control in a femtosecond-dephasing medium via quantum coherence
    H. Nishioka; K. Ueda
    Technical digest of International conference on Ultrafast optics 2001, 86-88, Jul. 2001, Peer-reviwed
    International conference proceedings, English
  • Absorption and emission control in a femtosecond-dephasing medium via quantum coherence
    H. Nishioka; K. Ueda
    Proc. of Ultrafast Optics, B74: S89-S92 Suppl. (2002), Jul. 2001, Peer-reviwed
    International conference proceedings, English
  • Quantum interference in a fs-dephasing medium induced by an intense hyper-continuum
    H. Nishioka; H. Koutaka; K. Ueda
    Conferece on Lasers and Electro-Optics 2001, CThM4, May 2001, Peer-reviwed
    International conference proceedings, English
  • Quantum interference effects in a femtosecond-dephasing medium
    H Nishioka; H Koutaka; K Ueda
    OPTICS EXPRESS, OPTICAL SOC AMER, 8, 11, 617-623, May 2001, Peer-reviwed, Coherence control in a lambda -type three-level system having an ultrafast (< 10 fs) dephasing time has been demonstrated. Coherences in the multilevel system were excited by an intense supercontinuum yielding terahertz Rabi frequencies. The coherence was controlled by changing the interaction phase between the excited coherences and the broadband light field in the double-pulse pumping scheme. (C) 2001 Optical Society of America.
    Scientific journal, English
  • Broadened gain bandwidth in diode-pumped Yb-doped materials at low temperature
    J Kawanaka; A Yasuhara; K Yamakawa; H Nishioka; K Ueda
    CLEO(R)/PACIFIC RIM 2001, VOL I, TECHNICAL DIGEST, IEEE, 84-85, 2001, Peer-reviwed, Each gain band width of diode-pumped Yb:glass and Yb:YLF was dramatically broadened to 50 nm at 8K from 20 nm at room temperature and to 35 nm from 20 nm, respectively.
    International conference proceedings, English
  • Coherence control in a fs-dephasing medium by means of differential phase pumping of ultra-broadband pulses
    H Nishioka; H Koutaka; K Ueda
    CLEO(R)/PACIFIC RIM 2001, VOL II, TECHNICAL DIGEST, IEEE, 648-649, 2001, Peer-reviwed, The coherent couplings and decoupling in multi-level and ultra-broadband materials (T-2<10 fs) have been demonstrated by means of differential phase pumping of intense and ultra-broadband pulses. Absorption suppression and gain enhancement was observed as a function of differential-Fourier phase of the intense ultra-broadband excitations.
    International conference proceedings, English
  • Quantum interference effects in a fs-dephasing medium
    H. Nishioka; H. Koutaka; K. Ueda
    International Quantum Electronics Conference 2000, Postdeadline paper IPD2-10, Nice Acropolis, France, IPD2-10, Sep. 2000, Peer-reviwed
    International conference proceedings, English
  • Energy extraction performance for a diode-pumped CPA system in Yb-doped materials at low temperature
    J Kawanaka; H Nishioka; N Inoue; Y Kubota; K Ueda
    XIII INTERNATIONAL SYMPOSIUM ON GAS FLOW AND CHEMICAL LASERS AND HIGH-POWER LASER CONFERENCE, SPIE-INT SOC OPTICAL ENGINEERING, 4184, 381-384, 2000, Peer-reviwed, The observed absorption and emission spectra of Yb:YLF at low temperature show that energy extraction efficiency is improved drastically with the reduced saturation fluence of 9 J/cm(2) and the expanded spectral width of 38 nm. Yb:glass also shows a similar temperature dependence of the spectral characteristics to that of Yb:YLF.
    International conference proceedings, English
  • High intensity coherent super-continuum radiation from optical channeling
    H Nishioka; K Ueda
    ICONO '98: FUNDAMENTAL ASPECTS OF LASER-MATTER INTERACTION AND NEW NONLINEAR OPTICAL MATERIALS AND PHYSICS OF LOW-DIMENSIONAL STRUCTURES, SPIE-INT SOC OPTICAL ENGINEERING, 3734, 10-14, 1999, An intense VUV-IR coherent light source based on the both spatial and temporal phase modulation in rare gas media induced by tera-watt laser field is presented. A spectra intensity of 1 GW/nm has been obtained from the UV to IR regions. An up-conversion broadband optical parametric amplifier based on the four-wave-mixing in a non-birefringence nonlinear materials has also been demonstrated for time gated spectra measurements with the ultra-broadband light source.
    International conference proceedings, English
  • Development of a compact, high-peak power ytterbium : glass laser
    S. Biswal J. Nees; J. Faure; A. Nishimura; H. Nishioka; G. Mourou
    Technical digest of CLEO'98, paper CWI2, CWI-12, 1998, Peer-reviwed
    International conference proceedings, English
  • UV to IR coherent light gneration by multichannel self-trapping in alkalli-halide crystales
    H. Nishioka; Y. Sasaki; K. Ueda
    Conference on Laser and Electro-optics, CThL50, May 1997
    International conference proceedings, English
  • Femtosecond continuously tunable second harmonic generation over the entire-visible range in orthorhombic acentric Gd-2(MoO4)(3) crystals
    H Nishioka; W Odajima; M Tateno; K Ueda; AA Kaminskii; AV Butashin; SN Bagayev; AA Pavlyuk
    APPLIED PHYSICS LETTERS, AMER INST PHYSICS, 70, 11, 1366-1368, Mar. 1997, Peer-reviwed, Second harmonic generation over the entire visible range in Nd3+ doped and undoped Gd-2(MoO4)(3) crystals under ultrashort hypercontinuum pumping is presented. The continuous tuning ranges from 487 to 790 nm in a single crystal. (C) 1997 American Institute of Physics.
    Scientific journal, English
  • Orthorhombic ferroelectric and ferroelastic Gd-2(MoO4)(3) crystal - A new many-purposed nonlinear and optical material: Efficient multiple stimulated Raman scattering and CW and tunable second harmonic generation
    AA Kaminskii; AV Butashin; HJ Eichler; D Grebe; R Macdonald; K Ueda; H Nishioka; W Odajima; M Tateno; J Song; M Musha; SN Bagaev; AA Pavlyuk
    OPTICAL MATERIALS, ELSEVIER SCIENCE BV, 7, 3, 59-73, Mar. 1997, Peer-reviwed, The nonlinear optical properties of a ferroelectric and ferroelastic beta'-Gd-2(MoO4)(3) laser crystal-host were studied by second harmonic generation (SHG) and stimulated Raman scattering (SRS) experiments using different laser sources for excitation. It is shown that the investigated crystals are very attractive for SHG with IR CW lasers as well as for continuously tunable SHG under illumination with a femtosecond hyper-continuum light source. Furthermore, up to five Stokes and five anti-Stokes lines have been obtained in picosecond SRS experiments with a total conversion efficiency of about 70%. Interaction of SHG and SRS, as well as a new effect, which may be called quasi-hyper SRS, have been observed with insulating crystal for the first time. We classify the beta'-Gd-2(MoO4)(3):Nd as a promising laser medium for pulsed and CW self-frequency doubling lasers.
    Scientific journal, English
  • Whole-visible continuously tunable SHG in Gd-2(MoO4)(3) crystals under femtosecond hypercontinuum coherent light pumping
    AA Kaminskii; H Nishioka; K Ueda; W Odajimu; M Tateno; Y Sasaki; SN Bagayev; AV Butashin; AA Pavlyuk
    LASER PHYSICS, INTERPERIODICA, 6, 4, 817-820, Jul. 1996, Peer-reviwed, Broadband continuously tunable (0.487 to 0.78 mu m) SHG in orthorhombic acentric Gd-2(MoO4)(3) and Gd-2(MoO4)(3) : Nd3+ single crystals under femtosecond hypercontinuum coherent light pumping is demonstrated. We have determined also the main parameters for SHG in these new nonlinear laser materials: the phase matching angle theta(m) = 65 +/- 5 degrees and the effective nonlinear coefficient [d(eff)] approximate to 1.9 x 10(-12) m/V for the ee-o interaction at lambda(f) = 1.06 mu m wavelength.
    Scientific journal, English
  • Orthorhombic gadolinium molybdate - A new nonlinear crystal for frequency doubling of 1 μm cw laser radiation
    A. A. Kaminskiǐ; K. Ueda; J. Song; H. Nishioka; N. Uehara; M. Musha; S. N. Bagaev; A. A. Pavlyuk
    Quantum Electronics, 26, 5, 379-380, May 1996, Peer-reviwed, A new nonlinear Gd2(MoO4)3 laser crystal was developed for generation of the second harmonic of 1 μm cw laser radiation. It is shown that Nd3+: Gd2(MoO4)3 is a promising material for cw crystal lasers with self-doubling of the emission frequency.
    Scientific journal, English
    DOI URL
  • Second-harmonic generation with Cherenkov-type phase matching in a bulk nonlinear LaBGeO5 crystal
    A. A. Kaminskiǐ; A. V. Butashin; H. Nishioka; K. Ueda; W. Odajima; M. Tateno; K. Sasaki
    Quantum Electronics, 26, 5, 381-382, May 1996, Peer-reviwed, Picosecond and femtosecond pumping of a bulk nonlinear LaBGeO5 crystal resulted in conical-ring generation of the second harmonic with Cherenkov-type phase matching. The 'Cherenkov rainbow' was observed for the first time.
    Scientific journal, English
    DOI URL
  • Intense coherent VUV radiation from a self-trapped ultra-short laser pulse
    H Nishioka; W Odajima; KI Ueda
    JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA, ELSEVIER SCIENCE BV, 80, 263-266, May 1996, Peer-reviwed, A new technique to generate super-wide-band, coherent, and high brightness radiation has been demonstrated The white-light ranging from IR to 150 nm was generated by a self-trapped femtosecond Ti:Al2O3 laser pulse in atmospheric pressure rare gases. Spectral intensities in the UV and the VIS regions are 100 MW/nm and 1 GW/nm, respectively. The beam divergence was measured to be 1 mrad.
    Scientific journal, English
  • Flat-spectrum superwhite light generation covering VUV to IR in optical trapping phenomena in rare-gas media
    K Ueda; H Nishioka; W Odajima; H Takuma
    LASER PHYSICS, INTERPERIODICA, 6, 2, 260-263, Mar. 1996, Peer-reviwed, Broadband continuum ranging from the IR to 150 nm has been generated in the self-trapping channels in atmospheric-pressure rare,eases. The spectra intensities of 1 GW/nm in the VIS, and 100 MW/nm in the UV were observed in argon. The multichannel self-trapping mechanism and the pulse broadening in the channels were discussed.
    Scientific journal, English
  • New manifestations of non-linear-optical interactions in KY(WO4)(2) and KGd(WO4)(2) laser crystals
    AA Kaminskii; H Nishioka; Y Kubota; K Ueda; H Takuma; SN Bagaev; AA Pavlyuk
    DOKLADY AKADEMII NAUK, MEZHDUNARODNAYA KNIGA, 346, 1, 33-36, Jan. 1996, Peer-reviwed
    Scientific journal, Russian
  • New manifestations of nonlinear optical interactions in KY(WO4)2 and KGd(WO4)2 laser crystals
    A. A. Kaminskii; H. Nishioka; Y. Kubota; K. Ueda; H. Takuma; S.N. Bagaev; A.A. Pavlyuk
    Physics-Doklady, 41, 1, 1-4, Jan. 1996, Peer-reviwed
    Scientific journal, English
  • Super-wide-band coherent light generation in multi-channeling propagation of tera-watt Ti: Sapphire laser pulses
    H Nishioka; W Odajima; Y Sasaki; K Ueda
    PROGRESS IN CRYSTAL GROWTH AND CHARACTERIZATION OF MATERIALS, PERGAMON-ELSEVIER SCIENCE LTD, 33, 1-3, 237-240, 1996, Broad band continuum ranging from the LR to 150 nm has been generated in the self-trapping channels in atmospheric pressure rare gases, The spectra intensities of 1 GW/nm in the VIS, and 100 MW/nm in the UV were observed in Argon. The multi-channel self-trapping mechanism and the pulse broadening in the channels were discussed.
    Scientific journal, English
  • 紫外波長可変レーザー結晶Ce3+:LiSrAlF6の吸収とレーザー発振特性
    久保田能徳; 館野元就; 西岡 一; 植田憲一
    レーザー研究, レ-ザ-学会, 24, 3, 353-359, 1996, Peer-reviwed
    Scientific journal, Japanese
    URL
  • High Efficiency Second Harmonic Generation of Self Doubling Laser Crystal Gd(MoO4)3 : Nd3+
    A.A. Kaminskii; K. Ueda; S.N. Bagaev; A.A. Pavlyuk; J. Song; H. Nishioka; N. Uehara; M. Musha
    Rs. J. Quantum Electron., 23, 389, 1996, Peer-reviwed
    Scientific journal, English
  • Ultra-broad-band continuum generation by a self-trapped ultra-short Ti : Al2O3 laser pulse
    H. Nishioka; W. Odajima; Y. Sasaki; K. Ueda
    TOPS on Advanced Solid-State Lasers, Optical Society of America, 1, vol.1 242-247, 1996
    International conference proceedings, English
  • Super-wide-band coherent light generation in multi-channeling propagation of tera-watt Ti: Sapphire laser pulses
    H Nishioka; W Odajima; Y Sasaki; K Ueda
    PROGRESS IN CRYSTAL GROWTH AND CHARACTERIZATION OF MATERIALS, PERGAMON-ELSEVIER SCIENCE LTD, 33, 1-3, 237-240, 1996, Peer-reviwed, Broad band continuum ranging from the LR to 150 nm has been generated in the self-trapping channels in atmospheric pressure rare gases, The spectra intensities of 1 GW/nm in the VIS, and 100 MW/nm in the UV were observed in Argon. The multi-channel self-trapping mechanism and the pulse broadening in the channels were discussed.
    Scientific journal, English
  • Ultrabroadband flat continuum generation in multichannel propagation of terrawatt Ti:sapphire laser pulses
    Hajime Nishioka; Wataru Odajima; Ken-ichi Ueda; Hiroshi Takuma
    Optics Letters, 20, 24, 2505-2507, 15 Dec. 1995, Peer-reviwed, Frequency detuning as a result of self-phase modulation that exceeds by four times the primary laser frequency is demonstrated. The white light, ranging from the IR to 150 nm, was generated by a self-trapped femtosecond Ti:Al2O3 laser pulse in atmospheric-pressure rare gases. Spectral intensities in the UV and the visible regions are 100 MWynm and 1 GWynm, respectively. The beam divergence was measured to be 1 mrad. © 1995, Optical Society of America.
    Scientific journal, English
    DOI URL
  • Ultrabroadband flat continuum generation in multichannel propagation of terrawatt Ti:sapphire laser pulses
    H Nishioka; W Odajima; K Ueda; H Takuma
    OPTICS LETTERS, OPTICAL SOC AMER, 20, 24, 2505-2507, Dec. 1995, Peer-reviwed, Frequency detuning as a result of self-phase modulation that exceeds by four times the primary laser frequency is demonstrated. The white light, ranging from the IR to 150 nm, was generated by a self-trapped femtosecond Ti:Al2O3 laser pulse in atmospheric-pressure rare gases. Spectral intensities in the UV and the visible regions are 100 MW/nm and 1 GW/nm, respectively. The beam divergence was measured to be 1 mrad. (C) 1995 Optical Society of America
    Scientific journal, English
  • EFFICIENT STIMULATED RAMAN-SCATTERING IN TETRAGONAL LASER CRYSTALLINE HOSTS NABI(MOO4)(2) AND NABI(WO4)(2)
    AA KAMINSKII; SN BAGAYEV; K UEDA; H NISHIOKA; Y KUBOTA; CHEN, X; A KHOLOV
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS, JAPAN SOC APPLIED PHYSICS, 34, 11A, L1461-L1463, Nov. 1995, Peer-reviwed, The efficient Raman scattering in two tetragonal laser crystalline hosts with disordered structure has been studied by Q-switched infrared laser pulse excitation. Raman spectra show that such disordered crystals have larger cross sections than those of typical ordered crystals. The effective Raman gain coefficients were estimated as (9 +/- 4) cm/GW for NaBi(MoO4)(2) (across c-axis) and as (8 +/- 4) cm/GW for NaBi(WO4)(2).
    Scientific journal, English
  • Supercontinuum with an intense plateau spectrum ranging from IR to VUV
    H. Nishioka; W. Odajima; K. Ueda
    CLEO '95. Conference on Lasers and Electro-Optics, 387, 1995, May 1995
    International conference proceedings, English
  • NEW OPTICAL PHENOMENA IN LASER INSULATING CRYSTAL HOSTS WITH 3RD-ORDER NONLINEAR SUSCEPTIBILITIES
    AA KAMINSKII; H NISHIOKA; Y KUBOTA; K UEDA; H TAKUMA; SN BAGAEV; AA PAVLYUK
    PHYSICA STATUS SOLIDI A-APPLIED RESEARCH, AKADEMIE VERLAG GMBH, 148, 2, 619-628, Apr. 1995, Peer-reviwed, Besides the multiple cascade stimulated Raman scattering, new optical nonlinear phenomena in laser crystal hosts are observed, in particular, in monoclinic KY(WO4)(2) and KGd(WO4)(2) compounds, under high density visible nano- and picosecond laser excitation in single-pass geometry. The first one is a ''laser rainbow'', a multiple co-axial ring Stokes Raman emission by four-wave mixing parametric processes, and the second one is the self-trapping (filamentation) of the propagating laser pump beam and Stokes generation.
    Scientific journal, English
  • Externally triggered intracavity Raman pulse generator
    H. Nishioka; K. Kimura; M. Satomi; K. Ueda
    CLEO '94. Summaries of Papers Presented at the Conference on Lasers and Electro-Optics. Vol.8. 1994 Technical Digest Series. Conference Edition (Cat. No.94CH3463-7) :, 424, 1994, May 1994
    International conference proceedings, English
  • HIGH COMPRESSION RATIO BACKWARD RAMAN CONVERSION FOR HIGH-BRIGHTNESS EXCIMER-LASER SYSTEMS
    H NISHIOKA; K KIMURA; K UEDA; H TAKUMA
    IEEE JOURNAL OF QUANTUM ELECTRONICS, IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 29, 7, 2251-2258, Jul. 1993, Peer-reviwed, A new scheme of backward Raman pulse compression, in which the backward first Stokes pulse is amplified under stationary conditions and the backward second Stokes under transient conditions by choosing an appropriate Raman medium, is proposed. The compression factor and efficiency are improved by insertion of selective absorbers for the second Stokes component. The feasibility of such a scheme is demonstrated by an experiment in which a 249 nm UV pulse of 20 ns duration has been compressed into a 30-ps pulse with an power gain of 150 and energy conversion efficiency of 22%. Higher compression ratio and higher efficiency is expected by under improved conditions.
    Scientific journal, English
  • MEASUREMENT OF MULTIPHOTON ABSORPTION AND ELECTRON AVALANCHE IN OPTICAL THIN-FILMS
    H NISHIOKA; T KAWASUMI; K UEDA; H TAKUMA
    LASER AND PARTICLE BEAMS, CAMBRIDGE UNIV PRESS, 11, 1, 55-64, 1993, Peer-reviwed, Measurements on nonlinear processes caused by multiphoton absorption and electron avalanche in optical thin films have been carried out using KrF lasers of 20-ns and 1.7-ps pulse duration. Multiphoton absorption of the order of 10(-7) J was detected by a photoacoustic signal, and the nonlinear growth of photo-induced current due to the electron avalanche was analyzed dynamically. The correlation between damage threshold and carrier lifetime was investigated for oxide and fluoride coatings.
    Scientific journal, English
  • ADVANCED TECHNIQUES OF HIGH-EFFICIENCY PULSE-COMPRESSION FOR KRF LASERS
    KI UEDA; H NISHIOKA; K KIMURA; H TAKUMA
    LASER AND PARTICLE BEAMS, CAMBRIDGE UNIV PRESS, 11, 1, 31-42, 1993, Peer-reviwed, A couple of advanced techniques of high-efficiency pulse compression for KrF lasers have been developed in our laboratory. As is well known, electron beam-excited KrF lasers have a capability of large output energy of 100- to 1,000-ns pulse duration. However, high-efficiency operation under a short-pulse input is difficult to achieve because of the reaction kinetics and short lifetime of KrF excimers. For developing ultrahigh peak-power lasers, the efficient pulse compression of ns to ps and ps to fs pulses is essential. We demonstrated advanced techniques, Raman pulse compression in a transient Raman regime, and pulse compression in saturated amplifiers with saturable absorbers.
    Scientific journal, English
  • SINGLE-SHOT UV AUTOCORRELATOR THAT USES A 2-PHOTON-INDUCED PHOTOACOUSTIC SIGNAL IN WATER
    H NISHIOKA; M ISHIGURO; T KAWASUMI; K UEDA; H TAKUMA
    OPTICS LETTERS, OPTICAL SOC AMER, 18, 1, 45-47, Jan. 1993, Peer-reviwed, A single-shot autocorrelation of an ultrashort UV pulse is measured by detecting a two-photon-induced photoacoustic signal in water. A supersonic wave representing the autocorrelation function is detected by a polyvinylidene fluoride piezoelectric film with a spatial resolution of less than 60 mum. The detection sensitivity is higher than that of a multiphoton-induced fluorescence method by approximately 2 orders of magnitude.
    Scientific journal, English
    DOI URL
  • 紫外光学薄膜の多光子吸収と電子雪崩の観測
    西岡 一; 河角孝行; 植田憲一; 宅間 宏
    レーザー研究, レ-ザ-学会, 20, 5, 344-354, 1992, Peer-reviwed
    Scientific journal, Japanese
    URL
  • High compression ratio backward Raman conversion for high brightness excimer laser systems
    H. Nishioka; K. Kumura; K. Ueda; H. Takuma
    Proc. of the IAEA technical committee meeting on drivers for ICF, 327-330, 1992
    International conference proceedings, English
  • Optical components of high power KrF lasers
    K. Ueda; H. Nishioka; H. Takuma; T. Izaw
    Proc. of the IAEA technical committee meeting on drivers for ICF, 339-348, 1992
    International conference proceedings, English
  • Toward the super high power KrF lasers : Generation of ultra-short pulse using saturable absorber acridine
    H. Nishioka; H. Yoneda; K. Ueda; H. Takuma
    Proc. of the IAEA technical committee meeting on drivers for ICF, 363-366, 1992
    International conference proceedings, English
  • DEVELOPMENT OF HIGH-POWER KRF LASER FOR ICF LASER DRIVER AND LASER INTERACTION EXPERIMENTS
    H YONEDA; H NISHIOKA; A SASAKI; K UEDA; T TAKUMA
    LASER INTERACTION AND RELATED PLASMA PHENOMENA, VOL 9, PLENUM PRESS DIV PLENUM PUBLISHING CORP, 9, 149-160, 1991, Peer-reviwed
    International conference proceedings, English
  • 2重可飽和色素とKrFレーザー増幅器を用いたサブピコ秒パルス発生
    西岡 一; 倉西英明; 植田憲一; 宅間 宏
    レーザー研究, The Laser Society of Japan, 14, 1, 122-129, 1991, Peer-reviwed, Sub-ps pulse generation by an absorber-amplifier system was demonstrated. A new scheme two-step pulse shaping was used to improve the compression ratio and stability. A uv saturable dye, acridine, having a low saturation energy and a low residual absorption was found to be suit-able for strong pulse shortening. We have obtained 400fs pulses with an output energy of 20mJ including ASE less than 0.1%.
    Scientific journal, Japanese
    URL
    DOI URL
  • Sub-ps KrF laser and its Application for Multi-photon absorption measurements
    H. Nishioka; T. Kawasumi; K. Ueda; H. Takuma
    Proceedings of LASER '90, 529-535, 1991
    International conference proceedings, English
  • Generation of 400 fs pulse in KrF laser amplifier with saturable absorber
    H. Nishioka; H. Kuranishi; K. Ueda; H. Takuma
    Proceedings of LASERS '89, 110-115, 1990
    International conference proceedings, English
  • UV SATURABLE ABSORBER FOR SHORT-PULSE KRF LASER SYSTEMS
    H NISHIOKA; H KURANISHI; K UEDA; H TAKUMA
    OPTICS LETTERS, OPTICAL SOC AMER, 14, 13, 692-694, Jul. 1989, Peer-reviwed
    Scientific journal, English
  • 紫外用可飽和色素アクリジンと短パルスKrFレーザーへの応用
    西岡 一; 倉西英明; 植田憲一; 宅間 宏
    レーザー研究, レ-ザ-学会, 17, 9, 652-661, 1989, Peer-reviwed
    Scientific journal, Japanese
    URL
  • 電子ビーム励起KrFレーザーの電子脱励起速度定数の測定
    西岡 一; 佐々木明; 倉嶋利雄; 植田憲一; 宅間 宏; 糟谷紘一
    レーザー研究, The Laser Society of Japan, 16, 9, 571-581, 1988, Peer-reviwed, The electron quenching rate of KrF* in an electron beam pumped laser has been studied by accurately measuring the saturation intensity in a mixture of Ar/Kr/F2=94/6/0.284. The input intensity of the measurements was widely varied from 100 W cm-2 (small signal region) to 100 MW cm-2 (absorption dominant region) in order to separate laser parameters which are small signal gain coefficient, absorption coefficient, and saturation intensity from the measured net gain coefficients. The gas pressure and the pump rate were varied in the range of 0.5 to 2.5 atm and 0.3 to 1.4 MW cm-3, respectively. The electron quenching rate constant of 4.5×10-7 cm3s-1 was obtained from the pressure and the pump rate dependence of the KrF* saturation intensity with the temperature dependence of the rate gas 3-body quenching rate as a function of gas temperature to the -3rd power. The small signal gain coefficients calculated with the determined quenching rate constants shows excellent agreement with the measurements.
    Scientific journal, Japanese
    URL
    DOI URL
  • Characteristics Of E-Beam Pumped Krf Laser System
    K. Ueda; H. Nishioka; H. Takuma
    Proceedings of SPIE - The International Society for Optical Engineering, 710, 7-14, 11 Mar. 1987, Peer-reviwed, The charcteristics of strongly saturated amplifier with a 100ns electron beam excitation are studied to determine the small signal gain, non-saturable absorption, and saturation intensity from 6% Kr to 95% Kr in Ar diluent. The pumping rates are maintained constant by adjusting the total pressure of gas mixtures to conpensate the different stopping power of Ar and Kr. Non-saturable absorption coefficients are measured at a full saturated amplifier between the zero gain intensity to 80MW/cm2. The small signal gain of 12.9%/cm and non-saturable absorption coefficient of 1.32%/cm are obtained for 95% Kr mixture. The saturation intensity, 2.2MW/cm2 for 6% Kr and 2.9MW/cm2 for 95% Kr mixture, derived from the zero gain intensity is in good agreement with the prediction of our computer model. Highest intrinsic efficiency of 12.2% is measured at high Kr concentration where the Extraction power density of 6.8MW/cm2 is obtained by the probe laser beam between 5-6MW/cm2. The formation efficiency for a wide range of Kr concentrations agrees with the theoretical prediction excellently as a function of Kr concentration. The details of the important parameters, gain, absorption, saturation intensity, maximum output, intrinsic efficiency, extraction efficiency, and formation efficiency will be discussed in this paper. © 1987 SPIE.
    Scientific journal, English
    DOI URL
  • Strongly saturated gain measurements and kinetics study of KrF lasers
    H. Nishioka; T. Kurashima; K. Ueda; H. Takuma
    Springer-Verlag Proceedings in Physics, 208-214, 1987
    International conference proceedings, English
  • ＵＶファラデー回転素子のＫｒＦレーザーへの応用
    植田憲一; 西岡 一; 久野裕彦; 神永 武; 宅間 宏
    レーザー研究, The Laser Society of Japan, 13, 10, 805-831, 1985, Peer-reviwed, The Faraday rotator which is transparent over ultra-violet wavelength region has been developed. At the wavelength of a Kr F laser the Verdet constants of Si O2, H2O and Na Cl are larger than the typical value of a Faraday glass for a glass laser system. A new technique to generate a repetetive pulse train has been demonstrated as an application of the UV Faraday rotator on the Kr F laser technology. An edemo-beam pumped Kr F laser with an intrademo-cavity Faraday rotator has produced an output with alternative polarization whose period is equal to the cavity round trip time by the injection of a short pulse polarized beam. The output was separated into a couple of polarized pulse trains by an external polarizer, when the pulse duration of the injection pulse was shorter than the cavity round trip time of l2ns. The pulse separation was 24ns and the typical pulse durationwas 12ns.
    Scientific journal, Japanese
    URL
    DOI URL
  • UVファラデー回転素子の開発
    西岡 一; 久野裕彦; 神永 武; 植田憲一; 宅間 宏
    レーザー研究, The Laser Society of Japan, 12, 11, 660-662, 1984, Peer-reviwed, A UV Faraday rotator for the high power KrF laser system and other UV excimer lasers has been developed for the first time. Pure water has high Verdet constant and high transmittance in UV region (up to 190 nm). Ninety degree polarization rotation of a KrF laser beam is obtained by passing through a 5 cm long quartz cell filled by pure water. Quartz rod has also been proved to be equally useful as a Faraday rotator for KrF lasers.
    Scientific journal, Japanese
    URL
    DOI URL

MISC

  • 真のコヒーレント光源を目指して
    西岡 一
    レーザー学会, 15 Aug. 2014, レーザー研究, 42, 8, 621-621, Japanese, Invited, Introduction scientific journal
  • Field Activities of Lasers
    YAMAKAWA Koichi; NISHIOKA Hajime
    The Laser Society of Japan, 15 Oct. 2010, rle, 38, 10, 743-743, Japanese, 0387-0200, 10027440336, AN00255326
    DOI URL
  • 多光子記録回折素子を用いた超高速光波位相補償と増幅
    西岡 一
    Nov. 2009, レーザー研究, 37, 11, 797-800, Japanese, Peer-reviwed, Invited, Introduction other
  • 超広帯域光パラメトリックチャープパルス増幅システム(6)―LD励起低温冷却型Yb:YLFチャープパルス増幅システムの高エネルギー化
    小川奏; 赤羽温; 青山誠; 辻公一; 河仲準二; 西岡一; 藤田雅之; 山川考一
    02 Sep. 2008, 応用物理学会学術講演会講演予稿集, 69th, 3, 963, Japanese, 200902226749025190
  • Development of a High-Intensity Few-Cycle Optical Parametric Chirped-Pulse Amplification System
    AOYAMA MAKOTO; AKAHANE YUTAKA; OGAWA KANADE; TSUJI KOICHI; SUGIYAMA AKIRA; HARIMOTO TETSUO; KAWANAKA JUNJI; NISHIOKA HAJIME; FUJITA MASAYUKI; YAMAKAWA KOICHI
    Aug. 2008, 日本原子力研究開発機構JAEA-Conf, 46-49, English, 200902225055731733
  • Few-Cycle, Multi-TW, Optical Parametric Chirped-Pulse Amplification System
    Ogawa K; Aoyama M; Akahane Y; Tsuji K; Harimoto T; Kawanaka J; Nishioka H; Fujita M; Yamakawa K
    We demonstrated ultra-broadband optical parametric chirped-pulse amplification using a picosecond broadband pump beam at a 1 μm wavelength region. Using two broadband pump beams, an amplification bandwidth of more than 350 nm was achieved in a type-I BBO crystal with a gain of 3.2x10^5., The Institute of Electronics, Information and Communication Engineers, 16 May 2008, Technical report of IEICE. LQE, 108, 51, 51-54, Japanese, 0913-5685, 110006866594
  • Ultra-broadband Optical Parametric Chirped Pulse Amplification By Two Broadband Pump Beams
    OGAWA KANADE; AOYAMA MAKOTO; AKAHANE YUTAKA; TSUJI KOICHI; KAWANAKA JUNJI; HARIMOTO TETSUO; NISHIOKA HAJIME; FUJITA MASAYUKI; YAMAKAWA KOICHI
    Feb. 2008, Annu Prog Rep Inst Laser Eng Osaka Univ, 2007, 241-242, English, 1343-3857, 200902268992677052
  • 超広帯域光パラメトリックチャープパルス増幅システム(5)‐光学基板による白色シード光発生‐
    赤羽温; 青山誠; 小川奏; 辻公一; 河仲準二; 西岡一; 藤田雅之; 山川考一
    04 Sep. 2007, 応用物理学会学術講演会講演予稿集, 68th, 3, 1106, Japanese, 200902258549803120
  • 超広帯域光パラメトリックチャープパルス増幅システム(4)‐励起光の角度分散によるパラメトリック増幅帯域の拡大‐
    小川奏; 赤羽温; 青山誠; 辻公一; 河仲準二; 西岡一; 藤田雅之; 山川考一
    04 Sep. 2007, 応用物理学会学術講演会講演予稿集, 68th, 3, 1106, Japanese, 200902288875216894
  • レーザー技術フロンティア「超広帯域コヒーレント光の応用」
    藤田雅之; 西岡 一
    Aug. 2007, プラズマ・核融合学会誌, 83, 8, 710-713, Japanese, Introduction other
  • 高出力・広帯域Yb:KYWチャープパルス再生増幅器
    小川奏; 赤羽温; 青山誠; 辻公一; 時田茂樹; 河仲準二; 西岡一; 山川考一
    27 Mar. 2007, 応用物理学関係連合講演会講演予稿集, 54th, 3, 1140, Japanese, 200902215112922154
  • Yb:YLF CPAレーザー励起超広帯域光パラメトリックチャープパルス増幅
    赤羽温; 青山誠; 小川奏; 辻公一; 杉山僚; 張本鉄雄; 河仲準二; 西岡一; 藤田雅之; 山川考一
    27 Mar. 2007, 応用物理学関係連合講演会講演予稿集, 54th, 3, 1158, Japanese, 200902202177232134
  • Development of Diode-Pumped Ultrahigh-Peak-Power Lasers
    NISHIOKA HAJIME; KAWANAKA JUNJI; YAMAKAWA KOICHI
    Mar. 2007, 日本原子力研究開発機構JAEA-Conf, 143-146, Japanese, 200902235075481283
  • レーザ装置の現状と将来
    西岡 一; 植田憲一
    Jan. 2007, レーザー協会誌, 32, 1, 2-9, Japanese, Introduction other
  • High-intensity few-cycle optical parametric chirped-pulse amplification system
    AOYAMA M; AKAHANE Y; OGAWA K; TSUJI K; HARIMOTO T; KAWANAKA J; NISHIOKA H; FUJITA M; YAMAKAWA K
    11 Dec. 2006, レーザー学会研究会報告 = Reports on the Topical meeting of the Laser Society of Japan, 356, 7-11, Japanese, 10018790733
  • Diode-Pumped Ytterbium-Doped Solid-State Lasers for Laser Fusion Reactor Driver
    KAWANAKA Junji; MIYANAGA Noriaki; TOKITA Shigeki; NISHIOKA Hajime; KAWASHIMA Toshiyuki; FUJITA Masayuki; YAMAKAWA Koichi; UEDA Ken-ichi
    08 Sep. 2006, 電気学会研究会資料. NE, 原子力研究会, 2006, 1, 19-23, Japanese, 10018782917
  • 超広帯域光パラメトリックチャープパルス増幅システム(1)‐低温冷却Yb:YLF CPAポンプレーザー‐
    赤羽温; 青山誠; 辻公一; 河仲準二; 西岡一; 山川考一
    29 Aug. 2006, 応用物理学会学術講演会講演予稿集, 67th, 3, 997, Japanese, 200902251671207550
  • Diode-Pumped Ytterbium-Doped Solid-State Lasers for High Energy Density Plasma
    KAWANAKA J.; TOKITA S.; NISHIOKA H.; KAWASHIMA T.; FUJITA M.; UEDA K.
    01 Jan. 2006, レーザー学会研究会報告 = Reports on the Topical meeting of the Laser Society of Japan, 342, 49-53, Japanese, 10017075897, AA11604414
  • Diode-Pumped Ytterbium-Doped Solid-State Lasers for High Energy Density Plasma
    KAWANAKA JUNJI; TOKITA SHIGEKI; NISHIOKA HAJIME; FUJITA MASAYUKI; YAMAKAWA KOICHI; UEDA KEN'ICHI
    2005, 電気学会光・量子デバイス研究会資料, OQD-05, 37-44, 7-11, Japanese, 200902261333931370
  • 高エネルギー密度超短パルスレーザー媒質
    西岡 一; 河仲準二
    日本オプトメカトロニクス協会, May 2004, 光技術コンタクト, 42, 5, 241-248, Japanese, Introduction other, 0913-7289, 40006255073, AN10075091
    URL
  • 高繰り返し動作を目的とした低温Yb:YLF再生増幅器出力の励起時間依存性
    河仲準二; 西岡一; 山川考一; 植田憲一
    28 Mar. 2004, 応用物理学関係連合講演会講演予稿集, 51st, 3, 1205, Japanese, 200902241045573817
  • Yb系全固体超短パルスレーザー 「半導体レーザー励起・高出力フェムト秒レーザー」
    西岡 一; 河仲準二
    日本工業出版, Nov. 2003, 光アライアンス（日本工業出版）, 14, 11, 21-25, Japanese, Introduction other, 0917-026X, 80016221473, AA11758790
    URL
  • 低温Yb:YLF結晶を用いた30‐mJ再生増幅器の開発
    河仲準二; 西岡一; 山川考一; 植田憲一
    30 Aug. 2003, 応用物理学会学術講演会講演予稿集, 64th, 3, 980, Japanese, 200902295357385417
  • Yb系全固体超短パルスレーザー
    西岡 一
    Jul. 2003, レーザー学会 第１４回レーザー応用セミナー テキスト, 14, 1-7, Japanese, Introduction other
  • 冷却Yb:LiYF4を用いたLD励起チャープパルス再生増幅器の開発
    河仲準二; 西岡一; 山川考一; 植田憲一
    24 Sep. 2002, 応用物理学会学術講演会講演予稿集, 63rd, 3, 942, Japanese, 200902163280603420
  • 光学界の今とこれから（ひろがる光の世界）
    西岡 一
    Apr. 2002, 光学（日本光学会５０周年記念号編）添付CD-ROM, 31, 4, Japanese, Introduction other
  • 低温Yb系固体材料を用いたLD励起再生増幅器の開発
    河仲準二; 西岡一; 山川考一; 植田憲一
    11 Sep. 2001, 応用物理学会学術講演会講演予稿集, 62nd, 3, 804, Japanese, 201202112983958095
  • 新しい原理のレーザー（自由電子レーザー）
    西岡 一
    Aug. 2001, 光学（日本光学会）, 30, 8, 533-537, Japanese, Peer-reviwed, Introduction other
  • Improved lawer operation of diode-pumped Yb-doped materials at low temperature.
    YASUHARA AKIO; KAWANAKA JUNJI; NISHIOKA HAJIME; YAMAKAWA KOICHI; UEDA KEN'ICHI
    18 May 2001, 電子情報通信学会技術研究報告, 101, 65(LQE2001 1-15), 43-48, Japanese, 0913-5685, 200902146699821299
  • 超短パルス光学「短パルス実験の経験より」
    西岡 一
    Jan. 2001, 日本光学会（応用物理学会）冬季講習会 東京大学生産技術研究所 資料AP002302, Japanese, Introduction other
  • 高平均出力CPA用Yb系固体材料の低温における熱伝導特性
    安原陽生; 河仲準二; 西岡一; 山川考一; 植田憲一
    03 Sep. 2000, 応用物理学会学術講演会講演予稿集, 61st, 3, 935, Japanese, 201202114152220459
  • 低温Yb系固体材料を用いた高利得・広帯域レーザー動作
    河仲準二; 西岡一; 山川考一; 植田憲一
    03 Sep. 2000, 応用物理学会学術講演会講演予稿集, 61st, 3, 930, Japanese, 201202147916579754
  • フェムト秒計測関連の動向―超広帯域光の発生と量子干渉による吸収放出制御―
    西岡 一
    Sep. 2000, 光技術動向調査委員会，光協会, ---, Japanese, Introduction other
  • 紫外域の光源と産業への応用「固体レーザーを用いた紫外光発生」
    西岡 一
    Jul. 1999, 日本分光学会 第35回夏期セミナー，東京大学山上会館, Japanese, Introduction other
  • 加工・計測技術の最新動向
    西岡 一
    Jul. 1999, 光技術動向セミナー，幕張メッセ, Japanese, Introduction other
  • Ybドープレーザ
    西岡 一
    1999, オプトニューズ113号,光協会, 20-21, Japanese, Introduction other
  • 「加工・計測：平成11年度光技術動向調査報告書」
    西岡 一
    1999, 光協会, 329-415, Japanese, Introduction other
  • 高強度レーザーパルスの自己束縛を用いたコヒーレント白色光の発生
    西岡 一; 植田憲一
    レーザーを用いると,大気のようにみだんその存在を意識しないような媒質でも非線形分極を生じ,光の伝搬方向やその周波数を著しく変化させる.ここでは,超高強度レーザー電場がもたらす気体媒質の屈折率変化を空間・時間の2つの方向からレーザー光の位相変調に応用した,高効率・超広帯域の波長変換法について紹介する.本光源は,真空紫外から赤外におよぶ白色スペクトルをもちながら,コヒーレンスをもっており,空間・時間ともに微小空間へのエネルギー集中が可能である., The Japan Society of Applied Physics, 1998, 応用物理, 67, 9, 1066-1069, Japanese, Peer-reviwed, Introduction other, 0369-8009, 130003430935
    URL
    DOI URL
  • 超短パルスレーザーによるコヒーレント白色光の発生
    西岡 一; 植田憲一
    1997, 光学, 26, 79, Japanese, Peer-reviwed, Introduction other
  • Orthorhombic gadolinium molybdate - A new nonlinear crystal for frequency doubling of one-micron cw laser emission.
    AA Kaminskii; K Ueda; SN Bagaev; AA Pavlyuk; J Song; H Nishioka; N Uehara; M Musha
    New nonlinear Gd-2(MoO4)(3) crystals for cw second harmonic generation of one-micron laser emission have been grown. It is shown, that the Gd-2(MoO4)(3):Nd3+ is promising candidate for cw self-doubling crystalline lasers., LEBEDEV PHYSICAL INST KVANTOVAYA ELEKTRONIKA JOURNAL, May 1996, KVANTOVAYA ELEKTRONIKA, 23, 5, 389-390, Russian, Report scientific journal, 0368-7147, WOS:A1996UT64400002
  • Optical second harmonic generation with the Cherenkov type phase matching in bulk nonlinear LaBGeO5 crystal.
    AA Kaminskii; H Nishioka; K Ueda; W Odajima; M Tateno; K Sasaki; AV Butashin
    Under pico- and femtosecond pumping the conical-ring second harmonic generation with the Cerenkov type phase matching are excited in bulk nonlinear LaBGeO5 crystal. The so-called Cerenkov rainbow phenomenon was observed for the first time., LEBEDEV PHYSICAL INST KVANTOVAYA ELEKTRONIKA JOURNAL, May 1996, KVANTOVAYA ELEKTRONIKA, 23, 5, 391-392, Russian, Report scientific journal, 0368-7147, WOS:A1996UT64400003
  • Report on CLEO/QELS’95. I. Coherent Light Sources, Lasers for Fusion and Strong Field Physics, Optical Interactions with Condensed Matter, and Nonlinear Optical Phenomena.
    大道博行; 実野孝久; 西岡一; 猿倉信彦; 石原一
    レ-ザ-学会, Jul. 1995, レーザー研究, 23, 7, 552-569, Japanese, 0387-0200, 10001617697, AN00255326
    URL
    DOI URL
  • CLEO'91/QELS'91 REPORT III. Gas Lasers, Laser Fusion, High Intensity Field Effects, Laser Spectroscopy.:Gas Lasers, Laser Fusion, High Intensity Field Effects, Laser Spectroscopy
    NISHIOKA Hajime; TANIWAKI Manabu; ASHIDATE Shu-ichi; OKAMOTO Tatsuki; NAKANO Hitoshi; MIYAZAKI Kenzo; OKADA Tasuo
    The Laser Society of Japan, 1991, rle, 19, No.7, 96, 7, 696-715, Japanese, 0387-0200, 130003701614
    URL
    DOI URL
  • 3p-ZF-12 Laser Pulse Compression by uv Saturable absorber
    Nishioka H.; Kuranishi H.; Ueda K.; Takuma H.
    The Physical Society of Japan (JPS), 12 Sep. 1989, 秋の分科会講演予稿集, 1989, 2, 337-337, Japanese, 110002049788, AA11823236
  • 30p-SB-11 Deveplopment of UV Saturable Absorber for KrF Laser Systems
    Nishioka H.; Kuranishi H.; Ueda K.; Takuma H.
    The Physical Society of Japan (JPS), 28 Mar. 1989, 年会講演予稿集, 44, 2, 329-329, Japanese, 110009792901, AN10453938
  • 1p-G1-10 KrFレーザーの吸収媒質の特定(量子エレクトロニクス)
    西岡 一; 浦壁 俊光; 倉島 利雄; 倉西 英明; 植田 憲一; 宅間 宏
    一般社団法人日本物理学会, 31 Mar. 1988, 年会講演予稿集, 43, 2, 310-310, Japanese, 110009724343, AN10453938
  • 29p-D-9 レーザー増幅特性によるKrF^*の電子脱励起速度定数の決定(量子エレクトロニクス)
    佐々木 明; 西岡 一; 植田 憲一; 宅間 宏; 糟谷 紘一
    一般社団法人日本物理学会, 27 Mar. 1987, 年会講演予稿集, 42, 2, 350-350, Japanese, 110009722337, AN10453938
  • ALTERNATING POLARIZATION LASER - A NEW SCHEME OF LASER OSCILLATION
    K UEDA; H NISHIOKA; H TAKUMA
    OPTICAL SOC AMER, Aug. 1986, JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS, 3, 8, P82-P83, English, Summary international conference, 0740-3224, WOS:A1986E625100093
  • 29a-CC-3 偏光回転KrFエキシマーレーザーの特性(量子エレクトロニクス)
    西岡 一; 佐々木 明; 植田 憲一; 宅間 宏
    一般社団法人日本物理学会, 29 Mar. 1986, 年会講演予稿集, 41, 2, 324-324, Japanese, 110009788325, AN10453938
  • 1p-T-8 ファラデー回転子挿入型KrFレーザーにおける多重パルス発振
    西岡 一; 森下 尚久; 神永 武; 安宅 博章; 植田 憲一; 宅間 宏
    一般社団法人日本物理学会, 13 Sep. 1985, 秋の分科会講演予稿集, 1985, 2, 346-346, Japanese, 110002016217, AA11823236
  • 1p-T-9 電子ビーム励起KrFレーザーの短パルスインジェクション
    佐々木 明; 神永 武; 西岡 一; 植田 憲一; 宅間 宏
    一般社団法人日本物理学会, 13 Sep. 1985, 秋の分科会講演予稿集, 1985, 2, 347-347, Japanese, 110002016218, AA11823236

Books and other publications

  • RGB３原色・白色光レーザーの開発
    西岡 一
    Japanese, Joint work, 超広帯域コヒーレント光, サイエンス＆テクノロジー, Jul. 2007
  • RGB３原色・白色光レーザーの開発
    植田憲一; 西岡 一
    Japanese, Supervisor, サイエンス＆テクノロジー, 2007
  • レーザーハンドブック
    レーザー学会
    Dictionary or encycropedia, Japanese, オーム社, 2005
  • ひろがる光の世界
    日本光学会
    Dictionary or encycropedia, Japanese, 日本光学会, 2002
  • レーザーの科学
    西岡 一
    Japanese, Joint work, 丸善, 1997

Lectures, oral presentations, etc.

  • マルチモード高出力緑色半導体レーザーのモード制御とビーム結合
    校條健太; 本村健治; 西岡一
    Poster presentation, Japanese, レーザー学会東京支部研究会, レーザー学会東京支部, 東京, Domestic conference
    Mar. 2020
  • 光受容タンパク質を用いた一次元光位置検出素子
    川原 哉子; 西岡 一; 岡田 佳子
    Oral presentation, Japanese, 日本光学会年次大会, 日本光学会, 大阪大学, Domestic conference
    05 Dec. 2019
  • 低利得光パラメトリック増幅による高コントラスト広帯域アイドラー光の発生
    吉井 健登; Guo Xiaoyang; 時田 茂樹; 吉田 実; 西岡 一; 河仲 準二
    Oral presentation, Japanese, 第６５回応用物理学会春期講演会, Domestic conference
    20 Mar. 2018
  • 広帯域OPCPAシステムのためのXPWによるシード光スペクトルの広帯域化
    岡本 岬; 吉井 健登; Xiaoyang Guo; 時田 茂樹; 川嶋 利幸; 西岡 一; 河仲 準二
    Oral presentation, Japanese, 第６５回応用物理学会春期講演会, Domestic conference
    19 Mar. 2018
  • 部分重水素置換KDP結晶を用いたOPCPAの開発 -希ガス充填中空ファイバーによる広帯域種光発生
    吉井健人; Xiaoyang Guo; 伊山功一; 時田茂樹; 吉田 実; 川嶋利幸; 西岡 一; 河仲準二
    Oral presentation, Japanese, 第77回応用物理学会秋季学術講演会, 応用物理学会, 朱鷺メッセ 新潟, Domestic conference
    14 Sep. 2016
  • OPCP励起用1J, 100Hz, sub-ns Yb:YAGレーザー増幅器の開発
    伊山功一; 時田茂樹; 西岡 一; 川嶋利幸; 兒玉了祐; 河仲準二
    Oral presentation, Japanese, 第77回応用物理学会秋季学術講演会, 応用物理学会, 朱鷺メッセ 新潟, Domestic conference
    14 Sep. 2016
  • Development of ultra-broadband frontend light source for OPCPA using partially-deuterated KDP crystals
    K. Yoshii; S. Tokita; X. Guo; K. Iyama; M. Yoshida; T. Kawashima, H; Nishioka; J. Kawanaka
    Oral presentation, English, The10th Asia-Pacific Laser Symposium (APLS2017) ,, Jeju, Korea, International conference
    12 May 2016
  • 高出力超短パルスOPCPAシステムの開発 ― 希ガス充填中空ファイバによる広帯域種光発生 ―
    吉井健登; 郭晓杨; 伊山功一; 時田茂樹; 吉田実; 川嶋利幸; 西岡一; 河仲準二
    Oral presentation, Japanese, 第63回応用物理学会春季学術講演会（東京工業大学）
    19 Mar. 2016
  • High power diode-pumped solid-state lasers by using cryogenic Yb:YAG composit ceramics
    Junji Kawanaka; Shigeki Tokita; Koichi Iyama; Toshiyuki Kawashima; Hajime Nishioka
    Invited oral presentation, English, The Second International Symposium on High Power Laser Science and Engineering (HPLSE 2016), Invited, International conference
    15 Mar. 2016
  • Development 1 J, 100 Hz, diode-pumped Yb:YAG ceramic laser for OPCPA pumping
    Junji Kawanaka; Shigeki Tokita; Koichi Iyama; Toshiyuki Kawashima; Hajime Nishioka
    Invited oral presentation, English, The 11th Laser Ceramics Symposium (LCS 2015), Invited, International conference
    30 Nov. 2015
  • 1 J, 100 Hz, diode-pumped Yb:YAG ceramic laser for OPCPA pumping
    Junji Kawanaka; Shigeki Tokita; Koichi Iyama; Toshiyuki Kawashima; Hajime Nishioka
    Invited oral presentation, English, The 11th Laser Ceramics Symposium (LCS 2015), Invited, International conference
    30 Nov. 2015
  • Pulse Stretching in a Cryogenic-Yb:YAG Regenerative Amplifier Using Transmission Gratings
    S. Tokita; S.I. Hwang; T. Kawashima; H. Nishioka; J. Kawanaka
    Oral presentation, English, The 4th Advanced Lasers and Photon Sources, Laser Society of Japan, Yokohama, International conference
    24 Apr. 2015
  • 1 J, 100 Hz Multiple Active-Mirror Laser Amplifier Using YAG /Yb:YAG Composite Ceramics
    S. Tokita; M. Divoky; S.I. Hwang; T. Kawashima; H. Nishioka; A. Lucianetti; J. Kawanaka
    Oral presentation, English, The 4th Advanced Lasers ana Photon Sources, Laser Society of Japan, Yokohama, International conference
    23 Apr. 2015
  • 差周波２フォノン励起による超広帯域光発生
    名原大翔; 西岡 一
    Oral presentation, Japanese, レーザー学会第３５回年次大会, レーザー学会, 東京, Domestic conference
    12 Jan. 2015
  • 1J，100Hz 低温Yb:YAG-TRAM マルチパス増幅器の開発
    時田茂樹; マーティン・ディボッキー; スンイン・ファン; 川嶋利幸; 西岡一; 河仲 準二
    Oral presentation, Japanese, レーザー学会学術講演会第35 回年次大会講演予稿集, Domestic conference
    11 Jan. 2015
  • 1J，100Hz 低温冷却Yb:YAG-TRAMマルチパス増幅器
    時田茂樹; マーティン ディボッキー; スンイン ファン; 川嶋利幸; 西岡一; 河仲準二
    Oral presentation, Japanese, 第７５回応用物理学会学術講演会, 応用物理学会, 北海道大学, Domestic conference
    20 Sep. 2014
  • ２フォノン干渉を用いた超広帯域光の発生
    名原大翔; 西岡 一
    Oral presentation, Japanese, 第14回レーザー学会東京支部研究会, レーザー学会, 東京, Domestic conference
    05 Mar. 2014
  • 周波数分解2光波混合による超短パルス光の合成
    森下 宰; 西岡 一
    Oral presentation, Japanese, 第１４回レーザー学会東京支部研究会, Domestic conference
    05 Mar. 2014
  • フェムト秒レーザーパルスのコヒーレント重畳
    名原大翔; 森下 宰; 西岡 一
    Oral presentation, Japanese, 応用物理学会,年次大会
    Sep. 2013
  • 過渡誘導ラマン散乱を用いた反ストークス光スペクトル制御
    西岡 一
    Oral presentation, Japanese, レーザー学会第３２回年次大会予稿集,レーザー学会第３２回年次大会
    Jan. 2012
  • 光学素子の非線形吸収とレーザー損傷
    西岡一
    Invited oral presentation, Japanese, 第１８回レーザー夏の学校, レーザー学会
    Aug. 2011
  • 単結晶ダイアモンド中の高次４光波混合
    西岡 一
    Oral presentation, Japanese, 応用物理学会,第72回応用物理学会学術講演会
    Aug. 2011
  • 超短パルスフーリエ位相のロックイン検出
    冨田 仁; 西岡 一
    Oral presentation, Japanese, レーザー学会学術講演会第３１回年次大会 講演予稿集,レーザー学会学術講演会第３１回年次大会
    Jan. 2011
  • パルス伸長・圧縮に正分散媒質を用いた高強度フェムト秒レーザー装置の開発
    赤羽温; 小川奏; 冨田仁; 西岡一; 山川考一
    Oral presentation, Japanese, レーザー学会,レーザー学会学術講演会第３１回年次大会
    Jan. 2011
  • 高分解能スペクトラルシェアリング干渉計
    冨田 仁; 西岡 一
    Oral presentation, Japanese, 応用物理学会,第６９会学術講演会
    Sep. 2008
  • 微少周期数回折光学素子による光電場波形制御
    西岡 一
    Invited oral presentation, Japanese, 第５回 超高速光エレクトロニクス研究会, 電子情報通信学会
    Aug. 2008
  • Automatic GDD Compensation and Amplification of Few-Cycle Pulses by Two-Photon Arranged Diffractive Optics
    Hajime Nishioka
    Invited oral presentation, English, The 20th Annual Lasers and Electro Optics Society Meeting, IEEE Laser and Electro-Optics Society, Lake Buena Vista, FL. , USA, International conference
    Oct. 2007
  • 超短パルス光の時間反転再生
    西岡 一
    Invited oral presentation, Japanese, レーザー学会第２７回年次大会, レーザー学会
    Jan. 2007
  • 周波数位相共役波による全光学群遅延分散補償
    西岡 一
    Invited oral presentation, Japanese, 第２回超高速フォトニクスシンポジウム 第５回超高速光エレクトロニクス研究会（共催）, 電子情報通信学会
    Jul. 2006
  • 半導体レーザー励起超高ピークレーザーの研究開発
    西岡 一; 河仲準二; 山川考一
    Public symposium, Japanese, 第７回光量子科学研究シンポジウム論文集, 日本原子力研究開発機構, 京都
    May 2006
  • 時間・周波数変換を用いた時間反転パルスの発生
    西岡 一
    Invited oral presentation, Japanese, 電子情報通信学会 第４回超高速光エレクトロニクス研究会
    Jan. 2004
  • コヒーレンス変換による 超短パルス光の光学制御
    西岡 一
    Others, 東海大学 物理学科コロキウム, 東海大学 物理学科コロキウム
    Dec. 2003
  • コヒーレンス変換による 超短パルス光の光学制御
    西岡 一
    Others, 東海大学 物理学科コロキウム
    Dec. 2003
  • コヒーレンス変換による周波数位相共役波の発生
    西岡 一
    Others, 第５回 光量子科学シンポジウム 論文集
    Nov. 2003
  • コヒーレンス変換による周波数位相共役波の発生
    西岡 一
    Others, Japanese, 第５回 光量子科学シンポジウム 論文集, 日本原子力研究所
    Nov. 2003
  • Kerr-lens mode-locked oscillation with cooled Yb:YLF and Yb:glass
    J. Kawanaka; K. Yamakawa; H. Nishioka; K. Ueda
    Public symposium, English, JAERI-Review 2001-046 Annual Report of KANSAI Research Establishment 2000, JAERI
    Feb. 2002
  • 周波数混合を用いた光エコー発生
    市橋祥子; 西岡 一
    Others, Japanese, レーザー学会東京支部研究会、北関東産学研究会第１４回産学官交流フォーラム予稿集
    Nov. 2001
  • 超広帯域光の発生とコヒーレント過渡現象の観測
    西岡 一
    Others, Japanese, レーザー学会東京支部研究会、北関東産学研究会第１４回産学官交流フォーラム予稿集
    Nov. 2001
  • LD励起低温Yb系材料による高効率レーザー動作
    安原陽生; 河仲準二; 西岡一; 山川考一; 植田憲一
    Others, Japanese, 電子情報通信学会技術研究報告
    Aug. 2001
  • フェムト秒レーザー技術概説
    西岡 一
    Others, Japanese, 平成１2年度光技術動向調査報告書光協会
    Apr. 2001
  • Yb系レーザー
    西岡 一
    Others, Japanese, 平成１2年度光技術動向調査報告書光協会
    Apr. 2001
  • 超高速光計測
    西岡 一
    Others, Japanese, 平成１2年度光技術動向調査報告書光協会
    Apr. 2001
  • 超広帯域レーザーを用いたフェムト秒緩和材料のコヒーレンス制御
    西岡 一; 神鷹太康; 植田憲一
    Others, Japanese, レーザー学会研究会資料,RTM-01-05
    Jan. 2001
  • Quantum interference effects in a fs-dephasing medium
    H. Nishioka; H. Koutaka; K. Ueda
    Public symposium, English, The second Symposium on Advanced Photon Research
    Nov. 2000
  • 加工・計測技術の最新動向
    西岡 一
    Others, Japanese, 光技術動向セミナー，光協会，幕張メッセ, 光技術動向セミナー，光協会，幕張メッセ
    Jul. 2000
  • 加工・計測技術の最新動向
    西岡 一
    Others, Japanese, 光技術動向セミナー，光協会，幕張メッセ
    Jul. 2000
  • Super-broadband, Ultrafast Optical Measurements
    H. Nishioka; K. Kusakabe; N. Kon; K. Ueda
    Public symposium, Japanese, Proc. of the first symposium of advanced photon research, Keihanna Plaza
    Nov. 1999
  • Super-broadband, Ultrafast Optical Measurements
    H. Nishioka; K. Kusakabe; N. Kon; K. Ueda
    Others, Japanese, Proc. of the first symposium of advanced photon research, Keihanna Plaza
    Nov. 1999
  • Energy extraction performance for CPA system in Yb-doped materials at low temperature
    J. Kawanaka; H. Nishioka; K. Ueda
    Public symposium, English, Proc. of the first symposium of advanced photon research,Keihanna Plaza
    Nov. 1999
  • Energy extraction performance for CPA system in Yb-doped materials at low temperature
    J. Kawanaka; H. Nishioka; K. Ueda
    Others, Japanese, Proc. of the first symposium of advanced photon research,Keihanna Plaza
    Nov. 1999
  • Energy extraction performance for CPA system in Yb-doped materials at low temperature
    J. Kawanaka; H. Nishioka; K. Ueda
    Others, Japanese, Proc. of the first symposium of advanced photon research Keihana Plaza, Proc. of the first symposium of advanced photon research,Keihanna Plaza
    Nov. 1999
  • Yb系固体材料の近赤外吸収・発光スペクトルの温度依存性
    河仲準二; 加藤義章; 西岡 一; 上原 昇; 植田憲一
    Others, Japanese, 応用物理学会予稿集2p-L-1
    Sep. 1999
  • 紫外域の光源と産業への応用「固体レーザーを用いた紫外光発生」
    西岡 一
    Others, Japanese, 日本分光学会 第35回夏期セミナー，東京大学山上会館
    Jul. 1999
  • 加工・計測技術の最新動向
    西岡 一
    Others, Japanese, 光技術動向セミナー，幕張メッセ
    Jul. 1999
  • LD励起Yb添加レーザー
    西岡 一
    Others, Japanese, 高機能全固体レーザ調査専門委員会，電気学会４月23日研究会資料
    Apr. 1999
  • LD励起Yb添加レーザー
    西岡 一
    Others, Japanese, 高機能全固体レーザ調査専門委員会，電気学会４月23日研究会資料, 高機能全固体レーザ調査専門委員会，電気学会４月23日研究会資料
    Apr. 1999
  • 超広帯域・超高速光計測
    西岡 一; 神鷹太康; 植田憲一
    Others, Japanese, レーザー学会研究会資料RTM-98-60
    1999
  • 新しいLD超起Ybドープレーザー
    Others, Japanese, 電気学会資料OQD-99-4
    1999
  • 新しいLD励起Ybドープレーザー
    Others, Japanese, 電気学会資料
    1999
  • Super-broadband, Ultrafast Optical Measurements
    Others, English, Proc. of the first symposium of advanced photon research Keihana Plaza
    1999
  • LD励起Ybドープレーザー
    西岡 一
    Others, Japanese, レーザー学会研究会資料RTM-99-24
    1999
  • High intensity coherent super-continuum radiation from optical channeling; X VI International conference of coherent and nonlinear optics
    H. Nsihioka; K. Ueda
    Invited oral presentation, Japanese, ICONO '98, Moscow, Russia, International conference
    Jul. 1998
  • 4光波混合広帯域光パラメトリック増幅器
    Others, Japanese, 電子情報通信学会研究会資料LQE98-77, 電子情報通信学会研究会資料LQE98-77
    1998
  • Development of a compact, high-peak power ytterbium : glass laser
    Others, English, Technical digest of CLEO'98, paper CWI2
    1998
  • High intensity coherent super-continuum radiation from optical channeling ; X (]G0006[) International conference of coherent and nonlinear optics
    Others, English, Proc. of SPIE
    1998
  • 4光波混合広帯域光パラメトリック増幅器
    Others, Japanese, 電子情報通信学会研究会資料LQE98-77
    1998
  • 気体中の自己トラップを用いた超広帯域コヒーレント光発生の研究
    植田憲一; 西岡 一; 米田仁紀
    Others, Japanese, 平成８・９年度科学研究費補助金 基盤研究（B）研究成果報告書
    1998
  • The hyper-continuum coherent light source and its application for high-speed, broad-band measurements, US.- Japan seminar
    H. Nishioka
    Invited oral presentation, English, Manipulation of matter by coherent light, Kusatsu Gunma Japan, Sep.1-5(1997), International conference
    Sep. 1997
  • Ultra-broad-band continuum generation by a self-trapped ultra-short Ti : Al2O3 laser pulse,
    Others, English, TOPS on Advanced Solid-State Lasers, Optical Society of America
    1996
  • Overview of scaling physics of high power KrF lasers
    Others, English, Proc. of the IAEA technical committee meeting on drivers for ICF
    1992
  • High compression ratio backward Raman conversion for high brightness excimer laser systems
    Others, English, Proc. of the IAEA technical committee meeting on drivers for ICF
    1992
  • Optical components of high power KrF lasers
    Others, English, Proc. of the IAEA technical committee meeting on drivers for ICF
    1992
  • Toward the super high power KrF lasers : Generation of ultra-short pulse using saturable absorber acridine
    Others, English, Proc. of the IAEA technical committee meeting on drivers for ICF
    1992
  • High compression ratio backward Raman conversion for high brightness KrF laser systems
    H. Nishioka; K. Kimura; K. Ueda
    Invited oral presentation, English, CLEO (Conference of Laser and ElectroOptics), Technical Digest of CLEO '91 paper Tha5(, International conference
    May 1991
  • Generation of 400 fs pulse in KrF laser amplifier with saturable absorber
    Others, English, Proceedings of LASERS '91
    1991
  • Sub-ps KrF laser and its Application for Multi-photon absorption measurements
    Others, English, Proceedings of LASER '90
    1990
  • Strongly saturated gain measurements and kinetics study of KrF lasers
    Others, English, Springer-Verlag Proceedings in Physics
    1988

Courses

  • 光工学実験実験第二
    The University of Electro-Communications
  • 光工学実験実験第二
    電気通信大学
  • 基礎電子回路
    The University of Electro-Communications
  • 基礎電子回路
    The University of Electro-Communications
  • 基礎電子回路
    電気通信大学
  • 光工学実験第二
    The University of Electro-Communications
  • 光工学実験第二
    電気通信大学
  • 基礎科学実験A
    The University of Electro-Communications
  • Optical measurements
    The University of Electro-Communications
  • 光エレクトロニクス実験第二
    The University of Electro-Communications
  • 光エレクトロニクス実験第二
    電気通信大学
  • 基礎科学実験A
    The University of Electro-Communications
  • 基礎科学実験A
    電気通信大学
  • 光計測特論
    The University of Electro-Communications
  • 光計測特論
    電気通信大学

Affiliated academic society

  • 日本光学会
  • 電子情報通信学会
  • Optical Society of America
  • 応用物理学会
  • 電気学会
  • レーザー学会

Research Themes

  • 光受容タンパク質を用いた単純細胞受容野型フィルター素子の作製と画像処理
    岡田 佳子; 長谷川 裕之; 西岡 一; 高橋 裕樹; 笠井 克幸
    日本学術振興会, 科学研究費助成事業, 電気通信大学, 基盤研究(B), 本研究は，光受容タンパク質の視覚機能をデバイスレベルで取り入れた視覚受容野型の画像フィルターを作製し，アナログ画像処理に適用すること，および視覚プロセスを構成論的に明らかにすることを目的とする．本年度は，タンパク質懸濁液をバイオナノインクとしてインクジェット印刷し，網膜神経節細胞受容野および脳の第一視覚野に存在する単純細胞受容野形状を3次元的に模倣した「グレースケール(多値化)DOG / Gaborフィルター」を実現し，アナログ画像処理および錯視検出に適用した．特にGaborフィルターを用いて，代表的な方向錯視であるCafe Wall 錯視を実験的に検出し，心理学実験および計算機シミュレーションと比較した．Cafe wall画像上をフィルター走査するだけで得られる畳み込み画像には，物理的には平行であるモルタル線部に右下がり，右上がりを示すtwisted codeが出現した．さらに錯視の強さに関するGaborフィルターの空間周波数および方位依存性を検討したところ，標準画像の場合には，フィルター長：タイル長が 0.66 以下の場合，および方位0度の場合に錯視が強調されることがわかった．Cafe Wall 錯視は方向依存性のある現象のため，視覚系の方向エンコード機構に基づいて説明することは妥当であり，本結果は錯視の強さが向きや線の長さを検出する神経細胞を模倣したGaborフィルターのサイズ（空間周波数）に依存することを示唆している．人間の目のエッジ検出機能と方向検知機能をソフトウェアや複雑な回路，電源を使わずに生体膜の特性だけで再現することに成功した．, 18H03258
    01 Apr. 2018 - 31 Mar. 2022
  • モード同期光学フォノンを用いた超広帯域光の発生
    西岡 一
    Principal investigator
    01 Apr. 2015 - 31 Mar. 2018
  • 超高電界ダイヤモンド光電素子の開発とその高出力THz光源への応用
    米田 仁紀; 馬場 和宏; 西岡 一; 植田 憲一
    日本学術振興会, 科学研究費助成事業, 電気通信大学, 基盤研究(B), 気相合成法(CVD)を用いた薄膜ダイヤモンドは大面積化が可能なこと、不純物制御が可能なこと、様々な電極構造をとりえることなどの利点があり、電気光学素子や高速デバイスとして期待されている。しかし、その多結晶性からの粒界のキャリヤーの動特性に対する影響が大きく、この詳細な物理を明らかにし、制御、膜質の改善を行うことが望まれていた。本研究では光伝導素子を構成させた超短パルスレーザー照射による電気パルス波形の観測、紫外ポンププローブ計測によるキャリヤー密度の時間発展の観測を行い、以下のような新しい知見を得た。 1.粒径の減少によりその粒界内のキャリヤー寿命、移動度は減少するが0.1〜10μmの粒径試料ではその依存性はγ=80ps(d/10μm)^<0.177>、μ=30cm^2/Vs(d/10μm)^<0.43>になることが明らかになった。 2.粒界内でキャリヤー寿命は大きく変化しており、また、5.0eV程度の紫外光照射ではトラップ準*の影響がキャリヤー寿命に大きな影響が出ることが分かった。 3.粒界影響による低移動度はダイヤモンドの持つ高い絶縁破壊強度により高電界印加させることでフォノン相互作用による飽和ドリフト速度まで増加させることが可能で影響は設計により低減させることが可能である。 また、これらCVDダイヤモンドの基礎特性が得られたことから光電動素子型の高出力THz光源の設計を行った。この際の最も重要な点は大面積化にともなう高電界印加可能な電極設計、出力THz光の空間コヒーレンス制御にある。THz光源でのダイヤモンドの優位性を確認するために実際に数千のギャップを2インチウエハ上に製作し、2ピコ秒の深紫外レーザーを用いて出力実験を行った。照射レーザーのバイナリーマスクによるコヒーレント制御性、電界の2乗スケーリング、波形の測定などが行われ、10mm^2の有効出射面積でこれまでのGaAsで達成された出力密度を越えるTHz波の発生に世界で初めて成功した。さらに高電界印加時の電流特性の評価から2インチウエハ前面に拡張することで出力強度としても最高値を得られることが明らかになった。, 09555008
    1997 - 1998
  • 気体中の自己トラップを用いた超広帯域コヒーレント光発生の研究
    植田 憲一; 米田 仁紀; 西岡 一
    日本学術振興会, 科学研究費助成事業, 電気通信大学, 基盤研究(B), 本研究は、気体の非線形屈折率を空間・時間の両面から波長変換法に応用し、真空紫外から赤外の光領域全域に渡る超広帯域な光強度のレーザー光の発生を行うことを目的とした。出力2TWのフェムト秒レーザーパルスを用いて気体中に自己束縛チャネルを形成し、高い光強度と長い相互作用長を実現した。このチャネル中での自己位相変調、4光波混合を利用して波長150-1650nmのスペクトル範囲で、コヒーレント光を得た。得られた光強度は真空紫外域で100MW/nm、紫外から赤外域で1GW/nmであった。ネオン、アルゴン、クリプトン、キセノンの異なる希ガス中のスペクトル強度、スペクトル帯域を測定した。同時に、ガス圧力、励起レーザー光強度に対する依存性を測定した。相互相関法を用いて、各波長の群遅延時間をフェムト秒の時間分解能で測定し、可視・赤外域では200fs以下のパルス幅を持つことを明らかにした。ビームの遠視野像を測定し、ビーム拡がり各は1mrad以下でありレーザーと同様の集光性能を持つことを示した。スペクトルの制限要因を考察するため、固体中における自己束縛実験と比較を行い、気体では2桁高い変換効率が得られること、非線形屈折率の大きさよりもイオン化エネルギーの大きさや屈折率分散がスペクトル幅を制限することを示した。自己位相変調に加え4光波混合による光パラメトリック増幅の位相整合条件を考察し、超広帯域光発生の位相整合条件について明らかにした。, 08454112
    1996 - 1998
  • サブヘルツ安定化レーザーを用いた超高性能光学素子計測技術の開発と応用
    植田 憲一; 潟岡 泉; 大橋 正健; 米田 仁紀; 西岡 一
    日本学術振興会, 科学研究費助成事業, 電気通信大学, 基盤研究(A), 超高安定レーザー計測では超高性能光学ミラーでの反射率、散乱強度の2次元空間分解測定だけでなく、共振器を構成する2枚のミラーのパラメータ分離が3枚合わせ法を考案することで初めて可能となった。これにより、絶対計測された超高品質ミラー単体という新たな基準器を手に入れることになり、今後の超高品質ミラー計測における適応性が大きく拡がった。光学パラメータ計測では屈折率の温度計係数が3桁以上の精度で測定ができるようになった。測定波長域も近紫外から近赤外域まで広がり、現在、特に高出力レーザー使用され結晶内の温度上昇が問題となっている非線形結晶の波長分散・温度係数測定や広いバンド幅を要求される超短パルスレーザー結晶などのパラメータを系統立てて測定しているところである。 イオンビームスパッタリング技術としては大面積化に適したRFガンの初期クラスター化のような現象が観測されたが、イオンガンの最適化を行うことで従来の小面積装置同等の膜質が得られる見込みがついている。 光学素子の新たな評価として超高真空チャンバー内での遠赤外レーザー加熱による脱ガス種測定およびこれによる有機汚染物質のクリーニングが提案され、実際のシステムが構築された。これにより蒸着膜内に含まれる水分量やその膜生成方法による差、各種クリーニング法(クリーニングペ-パ-洗浄、スピンクリーナ法、超純水洗浄、真空加熱法)による汚染除去の定量評価が初めて可能になった。現在光の散乱測定と同時計測することで得られた汚染除去量と光学パラメータの関係も明らかになりつつある。 以上のように、昨年から続けて行われてきた高品質ミラーならびに超高安定レーザーを利用した高精度測定技術の開発は同時に様々な全く新しい評価法、計測法を開発するという広がりを見せた。本研究で得られたシステム、方法、パラメータのすべてが今後の光学素子製造や評価の中核をなすことになるであろう。, 08555012
    1996 - 1997
  • 過渡ラマン散乱によるナノ秒からピコ秒への高効率パルス圧縮の研究
    植田 憲一; 宅間 宏; 西岡 一
    日本学術振興会, 科学研究費助成事業, 電気通信大学, 一般研究(B), 本研究では紫外レーザーの短パルス化を目的として、高い波長選択性を備えた光共振器と過渡ラマン散乱を組み合わせたパルス圧縮器の開発を行った。 1.過渡領域における後方ラマンパルス圧縮法の研究 (1)ストークスパルス幅が横緩和時間以下の領域では、ラマン利得の減少により高次ストークス光が抑制できることを示した。同時に、励起光線幅を制御して後方散乱利得帯域幅を広げ、横緩和時間以下の超短パルス光を定常増幅できることを示した。 (2)メタンをラマン媒質にしてKrFレーザーのパルス圧縮実験を行い、150倍(世界最高)の圧縮率を得た。 2.高い波長選択性を備えた高耐力共振器の開発 (1)屈折率差の小さい材料を用いて誘電体多層膜鏡を試作した。励起光、2次ストークス光に対し95%以上の透過率、1次ストークス光に対してフィネス400を両立した。 (2)光電流法を用いて誘電体多層膜鏡中の時間分解吸収観測を行った。光学材料の最適化し、レーザーコンディショニング機構を解明してレーザー耐力を4倍向上させた。 3.共振器の横モード制御と4光波混合によるエネルギー引き出し法の研究 (1)注入同期により共振器内1次ストークス光の横モードを制御し、励起光エネルギーの63%を1次ストークス光として蓄積することに成功した。 (2)励起光波長の短パルス光を共振器に注入して4光波混合を用いて短パルス高強度の2次ストークス光を発生させる原理を考案した。さらに、実験により原理の有効性を示した。, 04452102
    1992 - 1993
  • A^<2+>H^-型イオンエキシマによる高効率真空紫外光発生の研究
    植田 憲一; 宅間 宏; 米田 仁紀; 西岡 一
    日本学術振興会, 科学研究費助成事業, 電気通信大学, 一般研究(B), 1.希ガス・アルカリ系のイオンエキシマのab initio計算によって、ポテンシャル構造を考察し、原子番号に関係したスケ-リング則を求めた。中性エキシマから類推される結果とは違って、下準位は完全な自由状態でないことが判明した。 2.希ガス・アルカリ系のイオンエキシマでは81nm程度の最短波長が期待されることが判明した。原理的には結合ー結合遷移であるが、高い振動状態に対する遷移確率が極大をもつようになり、XeC1のようなquasiーexcimer発光が期待できることが分かった。 3.CsF+イオンエキシマのVUV発光が電子ビ-ム励起で観測され、従来の軟X線励起と異なった性質をもつことが分かった。BーX遷移(185nm)に加えてDーX遷移(152nm)の蛍光が30mbar以上のCsF蒸気圧まで観測され、振動準位の構造も分解された。 4.XeRb+(163nm),KrRb+(133nm)のVUV光の発生が観測され、ab initio計算と良い一致を示すことが明らかとなった。理論計算から求めたスペクトルの形は非対称スペクトル、構造の両面から実験結果と良い一致を与えた。 5.予備実験として行ったNa_2の3重項violet bandのエキシマ発光が観測された。励起強度を変化させるとスペクトルの狭帯域化が観測され、ASE増幅が起こっていることが確認された。理論計算による発光スペクトルは観測スペクトルを完全に説明した。 6.2段階可飽和吸収体による安定で高出力超短パルス発生技術を開発し、400フェムト秒、2.5テラワットのKrFレ-ザ-光を発生した。, 01460046
    1989 - 1990
  • 光音響・レーザー散乱の併用によるミラー損傷(プリダメージ)の研究
    植田 憲一; 宅間 宏; 西岡 一
    日本学術振興会, 科学研究費助成事業, 電気通信大学, 一般研究(C), 本研究は近年ますますその必要性が増大している短波長レーザー用の高耐力のミラーの開発の基礎的な研究として, 光学薄膜に生じているレーザーによる損傷または損傷以前の膜質の変化を光散乱や光音響信号によって検知解析しようとするものである. 以下に研究の成果をまとめる. 1.10^<-4>以下の吸収係数(k)をもつ各種の酸化物, フッ化物薄膜の吸収を光音響法で測定し, 紫外線レーザー用の膜材料の選択を行った. 2.10^<-2>〜10^<-3>の吸収係数の光学薄膜のレーザー損傷は, 光吸収-溶融破壊であることを, 理論/実験両面から明らかにした. 3.低吸収薄膜の光吸収で発生した内部応力で薄膜の基板からの剥離, クラッキングが生じることを明らかにした. 4.レーザー損傷強度の1/100以下の低レベルレーザー照射によって, 光学薄膜の吸収減少-損傷強度の向上が実現できることを示した. 5.吸収減少の曲線は際結晶過程の理論と良い一致を示し, 膜質改善は光学薄膜のアニーリング効果によるものであることが分かった. 6.多層膜のレーザー照射強度/光音響信号特性の中に, 複数の不連続点を観測し, 多層膜内の内部微小損傷がレーザー損傷強度の1/3程度で既に発生していることを発見した. 7.レーザー照射時の薄膜発光のスペクトルを観測し, レーザー照射による変化, 材料精製過程の影響を測定した. 8.レーザー損傷時には, 薄膜の固有発光スペクトルの異なる発光が観測されることを確認した. 破壊にともなう発光を高感度に観測すれば, 破壊強度をさらに高精度に決定できるだけでなく, 破壊の機構に関する情報を得ることが出来ると期待している., 62550027
    1987 - 1987