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glassesHosokawa, Shinya*; Kawakita, Yukinobu; Stellhorn, J. R.*; Pusztai, L.*; Blanc, N.*; Boudet, N.*; Ikeda, Kazutaka*; Otomo, Toshiya*
JPS Conference Proceedings (Internet), 33, p.011070_1 - 011070_7, 2021/03
Local- and intermediate-range atomic order in Ag ion conducting glasses Ag
(GeSe)
with x = 0.15, 0.28, 0.33, and 0.50 were investigated by using a combination of AXS, XRD, ND, and RMC modeling. By adding the ND pdf to AXS and XRD results, reasonable partial structure factors and partial pdf were obtained by the RMC procedure. In contrast to the previous AXS and RMC study, a large number of Ag-Ge and Ge-Ge correlations are observed in the first coordination shell region, which is consistent with an 
MD simulation. The coordination numbers around the Ge and Se mostly follow the 8-
rule over all Ag concentrations if Ag is not taken into account. With increasing the Ag concentration, the partial coordination numbers with Ge and Se atoms around Ag remarkably increases, while the Ag-Ag coordination number increases only slightly, indicating that the Ag conducting path is formed through the second neighboring Ag-Ag correlations.
Hasegawa, Noboru; Kawachi, Tetsuya; Kishimoto, Maki; Sukegawa, Kota*; Tanaka, Momoko; Tai, R. Z.*; Ochi, Yoshihiro; Nishikino, Masaharu; Nagashima, Keisuke; Kato, Yoshiaki*
Japanese Journal of Applied Physics, 48(1), p.012503_1 - 012503_6, 2009/01
Times Cited Count：6 Percentile：26.31(Physics, Applied)We evaluate the characteristics of a higher-order harmonics light as a seed X-ray amplified through the laser-produced X-ray amplifier. Narrow spectral bandwidth of the X-ray amplifier works as the frequency filter of the seed X-ray, resulting in that only the temporally coherent X-ray is amplified. Experimental investigation using the 29th-order harmonic light of the Ti:sapphire laser at a wavelength of 26.9 nm together with the neon-like manganese X-ray laser medium shows obvious spectral narrowing of the seed X-ray and amplification without serious diffraction effects on the propagation of the amplified X-ray beam. This implies that the present combination is potential to realize temporally coherent X-ray lasers, with the expected duration of several 100 fs.
Hasegawa, Noboru; Kawachi, Tetsuya; Sasaki, Akira; Kishimoto, Maki; Sukegawa, Kota; Tanaka, Momoko; Tai, R. Z.*; Ochi, Yoshihiro; Nishikino, Masaharu; Nagashima, Keisuke; et al.
Physical Review A, 76(4), p.043805_1 - 043805_5, 2007/10
Times Cited Count：20 Percentile：66.81(Optics)We firstly demonstrated the measurement of temporal profile of the amplification gain of the transient collisional excitation (TCE) X-ray laser with the solid target by use of X-ray diagnostic beam injection technique. In this experiment, higher-order harmonic light at a wavelength of 26.9 nm was injected into the neon-like manganese plasma as X-ray laser medium, and the amplified signal was observed. The obtained buildup time of the amplification gain was 23 ps measured from the time of the main pumping laser pulse, and the lifetime of the amplification gain was 27 ps. This result was in good agreement with the theoretical simulation by using an atomic kinetics code.
Kawachi, Tetsuya; Nagashima, Keisuke; Kishimoto, Maki; Hasegawa, Noboru; Tanaka, Momoko; Ochi, Yoshihiro; Nishikino, Masaharu; Kawazome, Hayato; Tai, R.; Namikawa, Kazumichi*; et al.
Proceedings of SPIE's International Symposium on Optics and Photonics 2005, Vol.5919, p.59190L_1 - 59190L_11, 2005/09
Recent results of the X-ray laser research in Advanced Photon Research (APR) Center in JAERI are reported. In the application of the nickel-like silver laser at a wavelength of 13.9 nm, we report the observation of the microscopic polarization clusters in ferroelectrics material such as BaTi03 by use of the X-ray speckle technique, and other experiments such as photo-ionization of inner-shell electrons are intoroduced. In the development of high quality X-ray laser beam, recently we demonstrated temporally coherent X-ray beam at 23.6 nm, in which the high-order harmonics light was injected into the Ne-like Mn X-ray amplifier. We also mention about the development of new X-ray laser driver laser, which is based on 2 beams of zig-zag slab Nd:glass lasers with 0.1 Hz repetition-rate, and each beam line can provide 10 J output energy, and 1 ps duration.
Tai, R.; Namikawa, Kazumichi; Sawada, Akikatsu*; Kishimoto, Maki; Tanaka, Momoko; Lu, P.*; Nagashima, Keisuke; Maruyama, Hiroshi*; Ando, Masami*
Physical Review Letters, 93(8), p.087601_1 - 087601_4, 2004/08
Times Cited Count：76 Percentile：89.42(Physics, Multidisciplinary)The polarization clusters existing in both the ferroelectric and the paraelectric phase of BaTiO are directly observed and characterized for the first time by a picosecond soft X-ray laser speckle technique. These dynamic clusters appear continuously across the Curie temperature Tc. The clusters' distance increases approximately linearly with temperature, while their mean size does not change significantly. The polarization exhibits a maximum at a temperature about 5 degree above Tc. The clusters' short-range correlation strength diverges as (T-Tc)
0.41
0.02 as temperature decreases toward Tc.
Nagashima, Keisuke; Tanaka, Momoko; Nishikino, Masaharu; Kishimoto, Maki; Kado, Masataka; Kawachi, Tetsuya; Hasegawa, Noboru; Ochi, Yoshihiro; Sukegawa, Kota*; Tai, R.; et al.
Applied Physics B, 78(7), p.927 - 932, 2004/05
We have succeeded in developing a laser-pumped X-ray laser with full spatial coherence at 13.9 nm. A highly directed X-ray laser beam with the divergence of 0.2 mrad was generated from the double target experiment, where a seeding light from the first laser medium was amplified in the second medium. The observed divergence is close to the diffraction limit value within a factor of two. The seeding light was amplified in the second medium without refraction influence and the gain coefficient was about 8 cm-1. From the measurement of visibility, it was found that the spatial coherent length is longer than the beam diameter. As an application of this coherent X-ray laser, we observed a surface microstructure of ferroelectric material, BaTiO and clarified a change of the microstructure near the Curie temperature.
Hasegawa, Noboru; Kawachi, Tetsuya; Utsumi, Takayuki*; Sasaki, Akira; Tanaka, Momoko; Kado, Masataka; Sukegawa, Kota*; Lu, P.; Kishimoto, Maki; Tai, R.; et al.
Japanese Journal of Applied Physics, Part 1, 43(5A), p.2519 - 2522, 2004/05
Times Cited Count：12 Percentile：45.03(Physics, Applied)We conducted high-precision measurements of the wavelength of the nickel-like silver X-ray laser in order to compare it with a theoretical wavelength. The reasons for using this laser are as follows: First, this laser line is in the wavelength region of Mo/Si multi-layer mirrors; therefore, this laser line is important for applications. Second, the strongamplification of this laser line has been obtained in our previous work, and the higher order line in the spectra obtained by our spectrometer can be used. Third, since silver is arelatively low-z material (z = 47), this wavelength is a ideal benchmark of atomic structural codes such as the Multiconfiguration Dirac-Fock (MCDF) code. The wavelength of the nickel-like silver X-ray laser was determined to be 13.887 nm. The comparison with MCDF codes shows that the present experimental result can work as a good benchmark of the accuracy of the codes.
Nagashima, Keisuke; Tanaka, Momoko; Nishikino, Masaharu; Kishimoto, Maki; Kado, Masataka; Kawachi, Tetsuya; Hasegawa, Noboru; Ochi, Yoshihiro; Sukegawa, Kota*; Tai, R.
Purazuma, Kaku Yugo Gakkai-Shi, 80(3), p.236 - 240, 2004/03
A laser-pumped X-ray laser with full spatial coherence has been developed for the first time. This X-ray laser has the wavelength of 13.9 nm and the beam divergence of 0.2 mrad. In the experiment, a seeding light from the first laser medium was amplified in the second medium, which worked as an active spatial filter. The observed beam divergence was close to the diffraction limited value within a factor of two. The seeding light was amplified in the second medium without refraction influence. The gain region of the second medium was far away from the target surface compared with that of the first medium and located in the considerably low density region. From the measurement of visibility, it was found that the spatial coherent length is longer than the beam diameter. It means that this X-ray laser beam is full spatial coherent.
Tang, H.; Daido, Hiroyuki; Kishimoto, Maki; Sukegawa, Kota*; Tai, R.; Mesesson, S.*; Tanaka, Momoko; Lu, P.; Kawachi, Tetsuya; Nagashima, Keisuke; et al.
Japanese Journal of Applied Physics, 42(2A), p.443 - 448, 2003/02
Times Cited Count：14 Percentile：50.33(Physics, Applied)no abstracts in English
by means of X-ray lasersTai, R.; Namikawa, Kazumichi*; Kishimoto, Maki; Tanaka, Momoko; Sukegawa, Kota*; Hasegawa, Noboru; Kawachi, Tetsuya; Kado, Masataka; Lu, P.; Nagashima, Keisuke; et al.
Physical Review Letters, 89(25), p.257602_1 - 267602_4, 2002/12
Times Cited Count：40 Percentile：81.12(Physics, Multidisciplinary)no abstracts in English
Lu, P.; Kawachi, Tetsuya; Kishimoto, Maki; Sukegawa, Kota*; Tanaka, Momoko; Hasegawa, Noboru; Suzuki, Masayuki; Tai, R.; Kado, Masataka; Nagashima, Keisuke; et al.
Optics Letters, 27(21), p.1911 - 1913, 2002/11
Times Cited Count：8 Percentile：39.79(Optics)We demonstrate a high gain nickel-like xenon ion x-ray laser using a gas puff target. The elongated x-ray laser plasma column was produced by irradiating the gas puff target with line-focused double picosecond laser pulses with a total energy of 18 J in a travelling-wave excitation scheme. Strong lasing at 9.98 nm was observed, and a high gain coefficient of 17.4 1/cm was measured on the transient collisionally excited 4d ミ 4p, J=0-1 transition for nickel-like xenon ion with target lengths up to 0.45 cm long. A weak nickel-like lasing line at a shorter wavelength of 9.64 nm was also observed with a gain coefficient of 5.9 1/cm.
Kawachi, Tetsuya; Kado, Masataka; Tanaka, Momoko; Sasaki, Akira; Hasegawa, Noboru; Kilpio, A.*; Namba, Shinichi; Nagashima, Keisuke; Lu, P.; Takahashi, Kenjiro; et al.
Physical Review A, 66(3), p.033815_1 - 033815_7, 2002/09
Times Cited Count：85 Percentile：93.02(Optics)A silver and tin slab targets were irradiated by a line-focused CPA glass laser light. In this experiment, the laser pulses consisted of two pulses with 4 ps duration, separated by 1.2 ns. Strong amplification in the nickel-like silver and tin x-ray lasers at the wavelengths of 13.9nm and 12.0nm was demonstrated with a pumping energy of 12 J and 14 J, respectively, and gain-saturation behaviors could be seen. A hydro-dynamics simulation coupled with a collisional-radiative model was performed under the present experimental condition, and the calculated result was compared with the experimental results.
Kato, Yoshiaki; Daido, Hiroyuki; Nagashima, Keisuke; Kawachi, Tetsuya; Hasegawa, Noboru; Tanaka, Momoko; Tang, H.; Tai, R.; Lu, P.; Kishimoto, Maki; et al.
AIP Conference Proceedings 641, p.31 - 39, 2002/00
no abstracts in English
SiKaneko, Koji; Stockert, O.*; Arndt, J.*; Borth, R.*; Skoulatos, M.*; Habicht, K.*; Kiefer, K.*; Schneidewind, A.*; Etzdorf, D.*; Takeuchi, Tetsuya*; et al.
no journal, ,
SiKaneko, Koji; Stockert, O.*; Arndt, J.*; Borth, R.*; Skoulatos, M.*; Habicht, K.*; Kiefer, K.*; Schneidewind, A.*; Etzdorf, D.*; Takeuchi, Tetsuya*; et al.
no journal, ,
