15 results on '"Noriaki Ohmae"'
Search Results
2. Optical frequency distribution using laser repeater stations with planar lightwave circuits
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Katsuya Oguri, Hidetoshi Katori, Atsushi Ishizawa, Hiromitsu Imai, Hideki Gotoh, Takashi Goh, Toshikazu Hashimoto, T. Akatsuka, Noriaki Ohmae, Tetsuomi Sogawa, Ichiro Ushijima, and Masao Takamoto
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Physics ,Optical lattice ,Optical fiber ,business.industry ,Clock rate ,Bandwidth (signal processing) ,Electrical engineering ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Laser ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,law.invention ,010309 optics ,Interferometry ,Optics ,Planar ,law ,0103 physical sciences ,0210 nano-technology ,business ,Electronic circuit - Abstract
We report a cascaded optical fiber link which connects laboratories in RIKEN, the University of Tokyo, and NTT within a 100-km region using a transfer light at 1397 nm, a subharmonic of the Sr clock frequency. The multiple cascaded link employing several laser repeater stations benefits from a wide feedback bandwidth for fiber noise compensation, which allows constructing optical lattice clock networks based on the master-slave configuration. We developed the laser repeater stations based on planar lightwave circuits to significantly reduce the interferometer noise for improved link stability. We implemented a 240-km-long cascaded link in a UTokyo–NTT–UTokyo loop using light sent from RIKEN via a 30-km-long link. In environments with large fiber noise, the link instability is 3 × 10−16 at an averaging time of 1 s and reaches 1 × 10−18 at 2,600 s.
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- 2020
3. An arm length stabilization system for KAGRA and future gravitational-wave detectors
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Norikatsu Mio, M. A. Barton, Masashi Ohkawa, Kai-Feng Chen, Soichiro Morisaki, K. Doi, D. Tuyenbayev, Wei-Tou Ni, Hong Wu, Kazuhiro Hayama, Jong-Dae Park, Hisa-aki Shinkai, Y. Hiranuma, N. Kimura, Zhaohuan Zhu, S. Miyoki, Chau Ron Wu, Se-Hong Oh, M. Marchio, M. Kamiizumi, M. Chan, B. H. Hsieh, Atsushi Nishizawa, Ryoji Takahashi, Yoichi Aso, C. Y. Lin, G. Ueshima, L. C.C. Lin, Koji Nagano, Takahiro Yamada, Takaaki Kajita, Yuki Inoue, Shuen De Wu, Kipp Cannon, Kentaro Komori, H. K. Lee, M. Ohashi, T. Shimoda, H Hayakawa, K. Izumi, Y. Tomigami, P. Jung, M. Fukunaga, Y. Huang, R. Shimizu, H. Chu, Y. M. Kim, T. Uehara, G-Z. Huang, A. Hagiwara, Hiroyuki Nakano, Y. Moriwaki, R. Bajpai, Jun'ichi Yokoyama, G. Ge, Takahiro Tanaka, Takaaki Yokozawa, Kei Kotake, Yoshiaki Himemoto, Keiko Kokeyama, F. E. Peña Arellano, Tetsuro Shishido, H. Pang, Y. Sakuno, M. Takeda, N. Kita, R. Nakashima, Yasufumi Kojima, Y. Sakai, Satoshi Tsuchida, Hideyuki Tagoshi, Y. Saito, Takayuki Tomaru, T. Tsang, Kentaro Somiya, Yoshio Arai, K. Sakai, Yuichiro Sekiguchi, Jianfang Wang, J. Kume, Hajime Sotani, Chunglee Kim, M. Nakano, L. W. Luo, Feng Li Lin, Yongheng Zhao, H. Vocca, Bungo Ikenoue, T. Yoshioka, Takahiro Yamamoto, Kuo-Chuan Pan, Hirotaka Takahashi, R. Flaminio, Nami Uchikata, R. Negishi, S. Oshino, S. Takano, K. Shimode, Masaki Ando, Tomotada Akutsu, T. Sekiguchi, C. Chen, Noriaki Ohmae, S. Sato, L. Baiotti, E. N. Tapia San Martin, E. Hirose, Tatsuya Narikawa, Akito Araya, K. Yamamoto, Nobuyuki Kanda, Sadakazu Haino, T. Ushiba, Y. Bae, K. Ueno, Mitsuhiro Fukushima, D. Tatsumi, S. Kanbara, Ping Huang, S. Eguchi, Takashi Uchiyama, Kunihito Ioka, Innocenzo M. Pinto, R. Kozu, Kyohei Kawaguchi, J. J. Oh, E. J. Son, L. Trozzo, Shuji Saito, Naoki Aritomi, Kenta Tanaka, Yi Chen, Akiteru Takamori, Kouji Nakamura, W. Ogaki, Naru Hirata, Chihiro Kozakai, H. Yuzurihara, T. Sato, M. H. P. M. van Putten, Z. Hong, Ayaka Shoda, T. Tomura, K. Tsubono, G. Kang, S. Bae, K. Miyo, H. Tanaka, Albert K. H. Kong, Yoshinori Fujii, Yutaro Enomoto, Ray-Kuang Lee, K. Kwak, Hyang Woon Lee, Simon Zeidler, F. Uraguchi, Yousuke Itoh, Yuta Michimura, A. Miyamoto, Rajesh Kumar, K. Kusayanagi, C. Ooi, Y. Obuchi, Y. Miyazaki, Sachiko Kuroyanagi, Nobuyuki Kawai, M. Leonardi, Guo-Chin Liu, R. Sugimoto, Hiroki Takeda, Haruki Kitazawa, Souichi Telada, T. Sawada, W. S. Kim, W-R. Xu, K. Hasegawa, H-S. Kuo, Naoko Ohishi, S. Shibagaki, Mitsuru Musha, Y-K. Chu, K. Yokogawa, Shigeo Nagano, Chin Guo Kuo, Koji Arai, Ken-ichi Oohara, A. Ueda, Sakae Araki, Osamu Miyakawa, S. Tanioka, K. Jung, Takamasa Suzuki, E. Capocasa, Koki Okutomi, S. Imam, Jinsook Kim, Toshihiro Tsuzuki, Kohei Inayoshi, N. Sago, T. Kawasaki, F. Travasso, Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), KAGRA, and Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules)
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Physics - Instrumentation and Detectors ,Optical fiber ,Physics and Astronomy (miscellaneous) ,Physics::Instrumentation and Detectors ,fibre: optical ,Physics::Optics ,cavity: optical ,01 natural sciences ,General Relativity and Quantum Cosmology ,law.invention ,gravitational-wave detector ,law ,noise: spectrum ,Astronomical interferometer ,95.75.Kk ,Multi-colour ,Physics ,Detector ,Instrumentation and Detectors (physics.ins-det) ,07.60.Ly ,Interferometry ,[PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc] ,noise: suppression ,Astrophysics - Instrumentation and Methods for Astrophysics ,performance ,interferometer ,FOS: Physical sciences ,General Relativity and Quantum Cosmology (gr-qc) ,Noise (electronics) ,Laser linewidth ,Optics ,0103 physical sciences ,KAGRA ,[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det] ,010306 general physics ,numerical calculations ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Astrophysics::Galaxy Astrophysics ,010308 nuclear & particles physics ,business.industry ,Gravitational wave ,stability ,04.80.Nn ,optics ,gravitational radiation detector ,laser ,interferometer: design ,Physics::Accelerator Physics ,95.55.Ym ,business ,Gravitational-wave detector ,Interferometer - Abstract
Modern ground-based gravitational wave (GW) detectors require a complex interferometer configuration with multiple coupled optical cavities. Since achieving the resonances of the arm cavities is the most challenging among the lock acquisition processes, the scheme called arm length stabilization (ALS) had been employed for lock acquisition of the arm cavities. We designed a new type of the ALS, which is compatible with the interferometers having long arms like the next generation GW detectors. The features of the new ALS are that the control configuration is simpler than those of previous ones and that it is not necessary to lay optical fibers for the ALS along the kilometer-long arms of the detector. Along with simulations of its noise performance, an experimental test of the new ALS was performed utilizing a single arm cavity of KAGRA. This paper presents the first results of the test where we demonstrated that lock acquisition of the arm cavity was achieved using the new ALS and residual noise was measured to be $8.2\,\mathrm{Hz}$ in units of frequency, which is smaller than the linewidth of the arm cavity and thus low enough to lock the full interferometer of KAGRA in a repeatable and reliable manner., Comment: 21 pages, 8figures
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- 2020
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4. Front Cover: Transportable Strontium Optical Lattice Clocks Operated Outside Laboratory at the Level of 10 −18 Uncertainty (Adv. Quantum Technol. 8/2021)
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Hidetoshi Katori, Toshihiro Shiimado, Kazuaki Fujii, Naoji Moriya, Kuniya Araki, Tetsuo Furumiya, Yuya Sakai, Takashi Muramatsu, Motohide Kokubun, Yosuke Takahashi, Ichiro Ushijima, Andrew Hinton, Masao Takamoto, Noriaki Ohmae, Naohiro Kamiya, and Ryuya Muramatsu
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Physics ,Nuclear and High Energy Physics ,Strontium ,Optical lattice ,business.industry ,chemistry.chemical_element ,Statistical and Nonlinear Physics ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,Optics ,Front cover ,Computational Theory and Mathematics ,chemistry ,Electrical and Electronic Engineering ,business ,Quantum ,Mathematical Physics - Published
- 2021
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5. Geopotential measurements with synchronously linked optical lattice clocks
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Masao Takamoto, Hiroshi Munekane, Ichiro Ushijima, Yuki Kuroishi, Tetsushi Takano, Atsushi Yamaguchi, Noriaki Ohmae, Basara Miyahara, Tomoya Akatsuka, and Hidetoshi Katori
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Physics ,Quantum optics ,Optical lattice ,Geopotential ,business.industry ,Geodesy ,Laser ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention ,010309 optics ,Gravitation ,Optics ,Theory of relativity ,law ,0103 physical sciences ,Master clock ,010306 general physics ,business ,Gravitational redshift - Abstract
Real-time geopotential measurements with two synchronously linked optical lattice clocks are demonstrated. A height difference between the two clocks separated by 15 km is determined, with an uncertainty of 5 cm, by means of a gravitational redshift. According to Einstein's theory of relativity, the passage of time changes in a gravitational field1,2. On Earth, raising a clock by 1 cm increases its apparent tick rate by 1.1 parts in 1018, allowing chronometric levelling3 through comparison of optical clocks1,4,5. Here, we demonstrate such geopotential measurements by determining the height difference of master and slave clocks separated by 15 km with an uncertainty of 5 cm. A subharmonic of the master clock laser is delivered through a telecom fibre6 to synchronously operate7 the distant clocks. Clocks operated under such phase coherence reject clock laser noise and facilitate proposals for linking clocks8,9 and interferometers10. Taken over half a year, 11 measurements determine the fractional frequency difference between the two clocks to be 1,652.9(5.9) × 10−18, consistent with an independent measurement by levelling and gravimetry11. Our system demonstrates a building block for an internet of clocks, which may constitute ‘quantum benchmarks’, serving as height references with dynamic responses.
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- 2016
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6. Frequency ratio of Yb and Sr clocks with 5 × 10−17 uncertainty at 150 seconds averaging time
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Hidetoshi Katori, Manoj Das, Noriaki Ohmae, Ichiro Ushijima, Nils Nemitz, Masao Takamoto, and Takuya Ohkubo
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Physics ,Frequency ratio ,Optical spectroscopy ,Quantum metrology ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,010309 optics ,Quantum mechanics ,0103 physical sciences ,Atomic and molecular physics ,010306 general physics ,Spectroscopy - Abstract
UTokyo Research掲載「異なる原子の光格子時計の短時間精密比較に成功」 URI: http://www.u-tokyo.ac.jp/ja/utokyo-research/research-news/rapid-comparison-of-optical-lattice-clocks.html, UTokyo Research "Rapid comparison of optical lattice clocks" URI: http://www.u-tokyo.ac.jp/en/utokyo-research/research-news/rapid-comparison-of-optical-lattice-clocks.html
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- 2016
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7. Construction of KAGRA: an underground gravitational-wave observatory
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S. Ota, M. Marchio, T. Furuhata, Yoichi Aso, J. Park, Shinji Miyoki, Y. Sasaki, Masashi Ohkawa, T. Kagawa, D. Jia, Kieran Craig, Y. Sugimoto, T. Uehara, Takaaki Yokozawa, M. Asano, Y. Liu, Akito Araya, Koki Okutomi, K. Kawaguchi, S. Yamaguchi, Nobuyuki Kanda, T. Miyamoto, Kazuyuki Tanaka, Takahiro Tanaka, H. K. Tanaka, Y. Saito, E. J. Son, Jinsook Kim, Yuichiro Sekiguchi, Hirotaka Takahashi, Eiichi Hirose, Kouji Nakamura, Toshihiro Tsuzuki, K. Awai, K. Miyake, Sho Fujibayashi, N. Uchikata, Akiteru Takamori, T. Miener, Kentaro Komori, F. Matsushima, Kazuhiro Yamamoto, Y. Kitaoka, Satoshi Tsuchida, M. Morioka, T. Wakamatsu, Mitsuhiro Fukushima, Tomotada Akutsu, Nobuyuki Matsumoto, K. Miyo, K. Oohara, N. Mio, Eric Hennes, Kazuhiro Agatsuma, Takashi Uchiyama, K. Shiga, A. Hagiwara, T. Ushiba, Tatsuya Kume, Innocenzo M. Pinto, Tomasz Starecki, Yoshinori Fujii, Y. Tachibana, C-Y. Lin, Kunihito Ioka, S. Harita, A. Shoda, Ken-ichi Nakao, R. Flaminio, Norichika Sago, H. Suwabe, Masatake Ohashi, Masako Kakizaki, J. Kato, Motoyuki Saijo, Simon Zeidler, T. Matsui, Yousuke Itoh, H. Kakuhata, Suguru Takada, Ken Ono, T. Shimoda, Ryoji Takahashi, J. V. van Heijningen, Y. Sato, Ayaka Kumeta, Takaaki Kajita, Yuki Susa, Yutaka Shikano, S. Ueki, S. Kanbara, T. Saito, K. Hashino, S. Yamamoto, M. Murakoshi, Hiroyuki Nakano, Yuki Inoue, Shinya Kanemura, Hyang Woon Lee, Tatsuya Narikawa, M. A. Barton, M. Fujisawa, Sakae Araki, T. Utsuki, T. Hirayama, F. E. Peña Arellano, Keiko Kokeyama, J. F. J. van den Brand, Osamu Miyakawa, Jun'ichi Yokoyama, L. Zheng, Mitsuru Musha, T. Arima, Yuta Michimura, Toshikazu Suzuki, Alessandro Bertolini, T. Ogawa, Y. Ono, Hideharu Ishizaki, Seiji Kawamura, Y. Muraki, M. Toritani, T. Kaji, A. Yanagida, Hideyuki Tagoshi, K. Sakai, A. Miyamoto, R. Goetz, S. Sato, D. Chen, C. L. Mueller, Makoto Uyeshima, Rajesh Kumar, Y. Hayashida, N. Hirata, Koji Nagano, M. Kamiizumi, L. Baiotti, Hirotaka Yuzurihara, W. Morii, Masa-Katsu Fujimoto, T. Yamamoto, T. Nonomura, Leo Tsukada, Hisa-aki Shinkai, M. Nakano, C. Tokoku, David B. Tanner, N. Arai, Daisuke Tatsumi, Yuya Kuwahara, K. Kobayashi, J. Kasuya, Yoshiyuki Obuchi, Kentaro Somiya, Soichiro Morisaki, Kyung-Suk Cho, Y. Zhao, N. Someya, A. Khalaidovski, K. Yano, K. Doi, Masaki Ando, Hironori Nakao, S. Atsuta, Maria Ilaria Del Principe, T. Narita, N. Ohishi, H. Tamura, Hyun Lee, Kyoko Okino, K. Hasegawa, B. Ikenoue, Kazunari Eda, Kazuhiro Hayama, Yasufumi Kojima, Masashi Hasegawa, Chunglee Kim, Fumihiro Uraguchi, Y. Sakakibara, Sadakazu Haino, K. Ueno, Ettore Majorana, John J. Oh, Koji Kubo, Kimio Tsubono, Nobuyuki Kawai, Hiroki Takeda, Souichi Telada, Tai Hyun Yoon, Y. Hashimoto, W. S. Kim, Wei-Tou Ni, S. Koike, T. Sekiguchi, Shuhei Mano, Y. Moriwaki, T. Sato, N. Kimura, Shigeo Nagano, Kei Kotake, Takayuki Tomaru, S. Saitou, Y. Oda, Takashi Nakamura, J. Guscott, Hideki Ishitsuka, Hideki Asada, Masaru Shibata, T. Yaginuma, Seog Oh, K. Hirai, S. Wada, M. H.P.M. Van Putten, M. Kaneyama, Yutaro Enomoto, Fumiko Kawazoe, J. Kim, Y. Akiyama, A. Suemasa, Y. Kataoka, Naoki Aritomi, Kazuaki Kuroda, R. DeSalvo, Noriaki Ohmae, (Astro)-Particles Physics, and KAGRA Collaboration
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Physics - Instrumentation and Detectors ,Gravitational-wave observatory ,Design ,Physics::Instrumentation and Detectors ,FOS: Physical sciences ,General Physics and Astronomy ,Laser ,General Relativity and Quantum Cosmology (gr-qc) ,01 natural sciences ,General Relativity and Quantum Cosmology ,gravitational-wave detector ,11. Sustainability ,0103 physical sciences ,ddc:530 ,KAGRA ,Interferometer ,Kamioka ,Aerospace engineering ,010306 general physics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Physics ,010308 nuclear & particles physics ,Gravitational wave ,business.industry ,Detector ,Instrumentation and Detectors (physics.ins-det) ,Vibration ,Interferometry ,seismic motion ,High Energy Physics::Experiment ,Astrophysics - Instrumentation and Methods for Astrophysics ,business - Abstract
著者人数: 227名 (所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 東谷, 千比呂), Number of authors: 227 (Affiliation. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS): Tokoku, Chihiro), Accepted: 2017-11-21, 資料番号: SA1170370000
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- 2018
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8. Direct Wavelength Measurement of the Visible M1 Transition in Ba7+ with a Novel Calibration Method
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Noriaki Ohmae, Naoki Kimura, Nobuyuki Nakamura, Michiharu Wada, Hidetoshi Katori, Kento Suzuki, Ryunosuke Kodama, Kunihiro Okada, and Shimpei Oishi
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Wavelength ,Materials science ,Optics ,Calibration (statistics) ,business.industry ,Condensed Matter Physics ,business - Published
- 2019
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9. Continuous-wave, single-frequency 229 nm laser source for laser cooling of cadmium atoms
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Hidetoshi Katori, J. M. Yarborough, Noriaki Ohmae, Yushi Kaneda, Yevgeny Merzlyak, Atsushi Yamaguchi, and Keitaro Hayashida
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Materials science ,Atomic Physics (physics.atom-ph) ,Physics::Optics ,FOS: Physical sciences ,01 natural sciences ,Physics - Atomic Physics ,Semiconductor laser theory ,law.invention ,010309 optics ,Optics ,law ,Laser cooling ,0103 physical sciences ,High harmonic generation ,Physics::Atomic Physics ,010306 general physics ,Optical lattice ,business.industry ,Amplifier ,Energy conversion efficiency ,Laser ,Atomic and Molecular Physics, and Optics ,Continuous wave ,Optoelectronics ,business ,Physics - Optics ,Optics (physics.optics) - Abstract
Continuous-wave output at 229 nm for the application of laser cooling of Cd atoms was generated by the 4th harmonic using two successive second harmonic generation stages. Employing a single-frequency optically pumped semiconductor laser as a fundamental source, 0.56 W of output at 229 nm was observed with a 10-mm long, Brewster-cut BBO crystal in an external cavity with 1.62 W of 458 nm input. Conversion efficiency from 458 nm to 229 nm was more than 34%. By applying a tapered amplifier as a fundamental source, we demonstrated magneto-optical trapping of all stable Cd isotopes including isotopes $^{111}$Cd and $^{113}$Cd, which are applicable to optical lattice clocks.
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- 2016
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10. Characteristics of Laser System Used in Large-Scale Cryogenic Gravitational Wave Telescope
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Norikatsu Mio and Noriaki Ohmae
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Physics ,Gravitational-wave observatory ,business.industry ,Gravitational wave ,Amplifier ,Surfaces and Interfaces ,Laser ,law.invention ,Power (physics) ,Telescope ,Interferometry ,Optics ,law ,Modulation ,General Materials Science ,Physics::Atomic Physics ,business ,Instrumentation ,Spectroscopy - Abstract
In order to detect a gravitational wave, a kilometer-scale interferometer with a high-power, single-frequency laser with extremely low noises is required. In the Japanese gravitational wave detector named Large-scale Cryogenic Gravitational wave Telescope (LCGT), a single-frequency laser with an output power of more than 100 W will be used. The laser system used in LCGT consists of a master laser, an amplifier, a pre-modecleaner, a modulation system, and a modecleaner. The system also includes stabilization systems for laser intensity and frequency. We have already developed most of them. This article describes the characteristics of the laser system used in LCGT and the current status of our developments.
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- 2011
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11. Frequency ratios of Sr, Yb and Hg based optical lattice clocks and their applications
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Hidetoshi Katori, Ichiro Ushijima, Tomoya Akatsuka, Manoj Das, Atsushi Yamaguchi, Masao Takamoto, Tetsushi Takano, Nils Nemitz, Takuya Ohkubo, Kazuhiro Yamanaka, and Noriaki Ohmae
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Physics ,Ytterbium ,Optical lattice ,Strontium ,Atomic Physics (physics.atom-ph) ,General Engineering ,FOS: Physical sciences ,Energy Engineering and Power Technology ,chemistry.chemical_element ,Effective nuclear charge ,Physics - Atomic Physics ,Wavelength ,chemistry ,Black-body radiation ,Atomic physics ,Sensitivity (electronics) ,Order of magnitude - Abstract
This article describes the recent progress of optical lattice clocks with neutral strontium ($^{87}$Sr), ytterbium ($^{171}$Yb) and mercury ($^{199}$Hg) atoms. In particular, we present frequency comparison between the clocks locally via an optical frequency comb and between two Sr clocks at remote sites using a phase-stabilized fibre link. We first review cryogenic Sr optical lattice clocks that reduce the room-temperature blackbody radiation shift by two orders of magnitude and serve as a reference in the following clock comparisons. Similar physical properties of Sr and Yb atoms, such as transition wavelengths and vapour pressure, have allowed our development of a compatible clock for both species. A cryogenic Yb clock is evaluated by referencing a Sr clock. We also report on a Hg clock, which shows one order of magnitude less sensitivity to blackbody radiation, while its large nuclear charge makes the clock sensitive to the variation of fine-structure constant. Connecting all three types of clocks by an optical frequency comb, the ratios of the clock frequencies are determined with uncertainties smaller than possible through absolute frequency measurements. Finally, we describe a synchronous frequency comparison between two Sr-based remote clocks over a distance of 15 km between RIKEN and the University of Tokyo, as a step towards relativistic geodesy., 11 pages, 5 figures, invited review article in Comptes Rendus de Physique 2015
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- 2015
12. All-polarization-maintaining, single-port Er:fiber comb for high-stability comparison of optical lattice clocks
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Martin E. Fermann, Hidetoshi Katori, Naoya Kuse, and Noriaki Ohmae
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Ytterbium ,Terahertz radiation ,FOS: Physical sciences ,Physics::Optics ,General Physics and Astronomy ,chemistry.chemical_element ,02 engineering and technology ,01 natural sciences ,Instability ,010309 optics ,Optical frequencies ,0103 physical sciences ,Physics ,Optical lattice ,business.industry ,General Engineering ,Spectral density ,021001 nanoscience & nanotechnology ,Polarization (waves) ,chemistry ,Optoelectronics ,0210 nano-technology ,business ,Order of magnitude ,Physics - Optics ,Optics (physics.optics) - Abstract
All-polarization-maintaining, single-port Er:fiber combs offer long-term robust operation as well as high stability. We have built two such combs and evaluated the transfer noise for linking optical clocks. A uniformly broadened spectrum over 135-285 THz with a high signal-to-noise ratio enables the optical frequency measurement of the subharmonics of strontium, ytterbium, and mercury optical lattice clocks with the fractional frequency-noise power spectral density of $(1-2)\times 10^{-17}$ Hz$^{-1/2}$ at 1 Hz. By applying a synchronous clock comparison, the comb enables clock ratio measurements with $10^{-17}$ instability at 1 s, which is one order of magnitude smaller than the best instability of the frequency ratio of optical lattice clocks., Comment: 14 pages, 4 figures
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- 2017
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13. Testing Lorentz Invariance with a Double-Pass Optical Ring Cavity
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Yuta Michimura, Wataru Kokuyama, Nobuyuki Matsumoto, K. Tsubono, Yoichi Aso, Masaki Ando, and Noriaki Ohmae
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Physics ,Ring (mathematics) ,Applied physics ,FOS: Physical sciences ,Physics::Optics ,General Relativity and Quantum Cosmology (gr-qc) ,Lorentz covariance ,General Relativity and Quantum Cosmology ,Double pass ,Metrology ,Nuclear physics ,High Energy Physics - Phenomenology ,High Energy Physics - Phenomenology (hep-ph) ,Optics (physics.optics) ,Physics - Optics - Abstract
We have developed an apparatus to test Lorentz invariance in the photon sector by measuring the resonant frequency difference between two counterpropagating directions of an asymmetric optical ring cavity using a double-pass configuration. No significant evidence for the violation was found at the level of $\delta c /c \lesssim 10^{-14}$. Details of our apparatus and recent results are presented., Comment: 4 pages, 1 figure. Presented at the Sixth Meeting on CPT and Lorentz Symmetry, Bloomington, Indiana, June 17-21, 2013
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- 2013
14. New limit on Lorentz violation using a double-pass optical ring cavity
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Kimio Tsubono, Yuta Michimura, Noriaki Ohmae, Nobuyuki Matsumoto, Wataru Kokuyama, Masaki Ando, and Yoichi Aso
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Electromagnetic field ,Physics ,Ring (mathematics) ,Lorentz transformation ,Scalar (mathematics) ,Null (mathematics) ,General Physics and Astronomy ,Resonance ,Physics::Optics ,FOS: Physical sciences ,General Relativity and Quantum Cosmology (gr-qc) ,General Relativity and Quantum Cosmology ,symbols.namesake ,Standard-Model Extension ,Quantum mechanics ,symbols ,Anisotropy ,Physics - Optics ,Optics (physics.optics) - Abstract
A search for Lorentz violation in electrodynamics was performed by measuring the resonant frequency difference between two counterpropagating directions of an optical ring cavity. Our cavity contains a dielectric element, which makes our cavity sensitive to the violation. The laser frequency is stabilized to the counterclockwise resonance of the cavity, and the transmitted light is reflected back into the cavity for resonant frequency comparison with the clockwise resonance. This double-pass configuration enables a null experiment and gives high common mode rejection of environmental disturbances. We found no evidence for odd-parity anisotropy at the level of $\delta c /c \lesssim 10^{-14}$. Within the framework of the Standard Model Extension, our result put more than 5 times better limits on three odd-parity parameters $\tilde{\kappa}^{JK}_{o+}$ and a 12 times better limit on the scalar parameter $\tilde{\kappa}_{\tr}$ compared with the previous best limits., Comment: 4 pages, 3 figures
- Published
- 2012
15. Thermal effects in high-power CW second harmonic generation in Mg-doped stoichiometric lithium tantalate
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Norikatsu Mio, Kohei Takeno, Sergey V. Tovstonog, Noriaki Ohmae, Toshio Katagai, Ikue Suzuki, Sunao Kurimura, and Shigenori Moriwaki
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Materials science ,Light ,Tantalum ,Lithium ,Green-light ,chemistry.chemical_compound ,Optics ,Materials Testing ,Scattering, Radiation ,Computer Simulation ,Magnesium ,Absorption (electromagnetic radiation) ,business.industry ,Lasers ,Temperature ,Second-harmonic generation ,Nonlinear optics ,Oxides ,Equipment Design ,Models, Theoretical ,Atomic and Molecular Physics, and Optics ,Equipment Failure Analysis ,chemistry ,Heat generation ,Lithium tantalate ,Harmonic ,Computer-Aided Design ,Optoelectronics ,Continuous wave ,business - Abstract
We investigated thermal behaviors of single-pass second-harmonic generation of continuous wave green radiation with high efficiency by quasi-phase matching in periodically poled Mg-doped stoichiometric lithium tantalate (PPMgSLT). Heat generation turned out to be directly related to the green light absorption in the material. Strong relation between an upper limit of the second harmonic power and confocal parameter was found. Single-pass second-harmonic generation of 16.1 W green power was achieved with 17.6% efficiency in Mg:SLT at room temperature.
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- 2008
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