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Asano, Shun*; Ishii, Kenji*; Matsumura, Daiju; Tsuji, Takuya; Kudo, Kota*; Taniguchi, Takanori*; Saito, Shin*; Sunohara, Toshiki*; Kawamata, Takayuki*; Koike, Yoji*; et al.
Physical Review B, 104(21), p.214504_1 - 214504_7, 2021/12
Times Cited Count:1 Percentile:7.22(Materials Science, Multidisciplinary)Hirobe, Daichi*; Sato, Masahiro*; Kawamata, Takayuki*; Shiomi, Yuki*; Uchida, Kenichi*; Iguchi, Ryo*; Koike, Yoji*; Maekawa, Sadamichi; Saito, Eiji
Nature Physics, 13(1), p.30 - 34, 2017/01
Times Cited Count:100 Percentile:96.77(Physics, Multidisciplinary)Yoshida, Masahiro*; Ishii, Kenji; Naka, Makoto*; Ishihara, Sumio*; Jarrige, I.*; Ikeuchi, Kazuhiko*; Murakami, Yoichi*; Kudo, Kazutaka*; Koike, Yoji*; Nagata, Tomoko*; et al.
Scientific Reports (Internet), 6, p.23611_1 - 23611_8, 2016/03
Times Cited Count:1 Percentile:11.30(Multidisciplinary Sciences)Yoshida, Masahiro*; Ishii, Kenji; Jarrige, I.*; Watanuki, Tetsu; Kudo, Kazutaka*; Koike, Yoji*; Kumagai, Kenichi*; Hiraoka, Nozomu*; Ishii, Hirofumi*; Tsuei, K.-D.*; et al.
Journal of Synchrotron Radiation, 21(1), p.131 - 135, 2014/01
Times Cited Count:3 Percentile:18.87(Instruments & Instrumentation)Wakimoto, Shuichi; Ishii, Kenji; Kimura, Hiroyuki*; Ikeuchi, Kazuhiko*; Yoshida, Masahiro*; Adachi, Tadashi*; Casa, D.*; Fujita, Masaki*; Fukunaga, Yasushi*; Gog, T.*; et al.
Physical Review B, 87(10), p.104511_1 - 104511_7, 2013/03
Times Cited Count:10 Percentile:43.17(Materials Science, Multidisciplinary)Yoshida, Masahiro; Ishii, Kenji; Ikeuchi, Kazuhiko*; Jarrige, I.; Murakami, Yoichi*; Mizuki, Junichiro; Tsutsui, Kenji; Toyama, Takami*; Maekawa, Sadamichi*; Kudo, Kazutaka*; et al.
Physica C, 470(Suppl.1), p.S145 - S146, 2010/12
Times Cited Count:4 Percentile:21.87(Physics, Applied)Imazono, Takashi; Sano, Kazuo*; Suzuki, Yoji; Kawachi, Tetsuya; Koike, Masato
AIP Conference Proceedings 1234, p.347 - 350, 2010/06
Times Cited Count:3 Percentile:75.67(Physics, Applied)Linear polarization measurements were carried out using a newly developed soft X-ray polarimeter and ellipsometer (SXPE) for complete polarization analysis at a soft X-ray beamline (BL-11) of the SR Center, Ritsumeikan University, Japan. A Mo/Si multilayer mirror was deposited on the surface of a Si(111) substrate by an ion beam sputtering method. It was cut into two pieces which were then used as reflection-type polarizers. When the incident wavelength was scanned from 12.4 nm to 14.8 nm by a Monk-Gillieson type varied-line-spacing grating monochromator of the BL-11, the angles of incidence of both the Mo/Si multilayer polarizers in the SXPE were also varied from 37.5 to 52.3
. The polarizances depended strongly on the wavelength, and the best performance of over 99% was obtained in the vicinity of 14 nm. Using these polarizers, we assessed that the degree of linear polarization of the BL-11 was almost constant at 85-88% in the measured wavelength range.
Imazono, Takashi; Sano, Kazuo*; Suzuki, Yoji; Kawachi, Tetsuya; Koike, Masato
Memoirs of the SR Center Ritsumeikan University, (12), p.87 - 100, 2010/05
A novel apparatus for polarimetric and ellipsometric measurements for the complete polarization analysis in the soft X-ray (SX) region, which is based on the rotating-analyzer ellipsometry by using six independently movable drive shafts, has been designed, constructed, and installed in BL-11. Linear polarization measurement has been demonstrated using two identical Mo/Si multilayer polarizers. The incident wavelength was scanned from 12.4 nm to 14.8 nm by a VLS-PGM of BL-11, and the angles of incidence of both polarizers were also varied from 37.5 to 52.3
. The best performance of polarizers has been determined to be over 99% at 13.9 nm, and the degree of linear polarization has been assessed to be 85-88% in the measured wavelength range for the first time since the completion of the beamline. This means that BL-11 is upgraded as the comprehensive evaluation beamline for optical elements including polarizing elements for use in the SX region.
Hiraka, Haruhiro*; Hayashi, Yoichiro*; Wakimoto, Shuichi; Takeda, Masayasu; Kakurai, Kazuhisa; Adachi, Tadashi*; Koike, Yoji*; Yamada, Ikuya*; Miyazaki, Masanori*; Hiraishi, Masatoshi*; et al.
Physical Review B, 81(14), p.144501_1 - 144501_6, 2010/04
Times Cited Count:15 Percentile:54.84(Materials Science, Multidisciplinary)Imazono, Takashi; Suzuki, Yoji; Sano, Kazuo*; Koike, Masato
Spectrochimica Acta, Part B, 65(2), p.147 - 151, 2010/02
Times Cited Count:2 Percentile:14.49(Spectroscopy)To meet the needs we have been developing an apparatus to evaluate polarization abilities of multilayer- and crystal-types polarizing elements and determine the polarization state of light in 1 keV region. The 8-axis goniometer called the polarization analysis-unit is equipped in this apparatus and consists of a phase shifter-unit and an analyzer-unit. All axes can be driven with HV compatible stepping motors. Both reflection- and transmission-types samples are available on P and A. Therefore, this apparatus makes it possible to carry out not only conventional reflection and transmission measurements but also four scanning modes which are double- reflections and transmissions, and transmission-reflection and vice versa.
Imazono, Takashi; Sano, Kazuo*; Suzuki, Yoji; Kawachi, Tetsuya; Koike, Masato
Review of Scientific Instruments, 80(8), p.085109_1 - 085109_8, 2009/08
Times Cited Count:18 Percentile:59.95(Instruments & Instrumentation)A new apparatus for polarimetric and ellipsometric measurements based on the rotating-analyzer method in the soft X-ray region has been designed, constructed, and installed in the soft X-ray beamline BL-11 at the SR Center of Ritsumeikan University, Shiga, Japan. It can realize the optical configurations for the complete polarization analysis by using six independently movable drive shafts. A demonstration of the capabilities of the apparatus has been performed using Mo/Si multilayer polarizers deposited by an ion beam sputtering method. It is for the first time shown that the degree of linear polarization of monochromatized light from the BL-11 is approximately 87% at 92 eV since the beamline has been constructed.
Wakimoto, Shuichi; Kimura, Hiroyuki*; Ishii, Kenji; Ikeuchi, Kazuhiko; Adachi, Tadashi*; Fujita, Masaki*; Kakurai, Kazuhisa; Koike, Yoji*; Mizuki, Junichiro; Noda, Yukio*; et al.
Physical Review Letters, 102(15), p.157001_1 - 157001_4, 2009/04
Times Cited Count:25 Percentile:74.85(Physics, Multidisciplinary)Risdiana*; Adachi, Tadashi*; Oki, Naoki*; Yairi, Satoshi*; Tanabe, Yoichi*; Omori, Keisuke*; Suzuki, Takao*; Watanabe, Isao*; Koda, Akihiro*; Higemoto, Wataru; et al.
Physica C, 460-462(2), p.874 - 875, 2007/09
Times Cited Count:3 Percentile:17.80(Physics, Applied)Zero-field muon-spin-relaxation measurements have been carried out for LaSr
Cu
Zn
O
(LSCO)with
= 0-0.10 in the overdoped regime up to
= 0.30, in order to investigate whether the dynamical stripe correlations are pinned and stabilized even for the overdoped LSCO or not. It has been found that the Zn-induced slowing down of the Cu-spin fluctuations is weakened with increasing
but takes place in the overdoped regime and disappears at
= 0.30. This suggests that the stripe-pinning model holds good in the whole superconducting regime of LSCO and that there is no quantum critical point at
0.19.
Ishii, Kenji; Tsutsui, Kenji*; Toyama, Takami*; Inami, Toshiya; Mizuki, Junichiro; Murakami, Yoichi*; Endo, Yasuo*; Maekawa, Sadamichi*; Kudo, Kazutaka*; Koike, Yoji*; et al.
Physical Review B, 76(4), p.045124_1 - 045124_7, 2007/07
Times Cited Count:20 Percentile:63.32(Materials Science, Multidisciplinary)(La,Sr,Ca)Cu
O
is an attractive material in connection with high-
superconductivity because Sr
Ca
Cu
O
becomes a superconductor under high pressure without the CuO
planes. We present RIXS at the Cu
-edge of (La,Sr,Ca)
Cu
O
focusing on the momentum dependence of interband excitation across the Mott gap and the intraband excitation below the gap as a function of hole concentration. The experimental results are consistent with the theoretical predictions.
Matsuda, Masaaki; Kakurai, Kazuhisa; Kurogi, Shogo*; Kudo, Kazutaka*; Koike, Yoji*; Yamaguchi, Hirotaka*; Ito, Toshimitsu*; Oka, Kunihiko*
Physical Review B, 71(10), p.104414_1 - 104414_8, 2005/03
Times Cited Count:13 Percentile:49.87(Materials Science, Multidisciplinary)no abstracts in English
Yoshida, Masahiro; Ishii, Kenji; Jarrige, I.; Ikeuchi, Kazuhiko; Murakami, Yoichi*; Mizuki, Junichiro; Tsutsui, Kenji; Toyama, Takami*; Maekawa, Sadamichi*; Kudo, Kazutaka*; et al.
no journal, ,
no abstracts in English
Imazono, Takashi; Sano, Kazuo*; Suzuki, Yoji; Kawachi, Tetsuya; Koike, Masato
no journal, ,
It is important for studies using polarized soft X-rays to obtain the information on the polarization state of polarized light in advance. No supply of polarizing element practicable in the energy region of 0.7-0.9 keV, which is in the vicinity of the L-edges of 3d transition metals, makes it difficult to evaluate the polarization state of the actual light so far. In order to perform polarization measurement, a soft X-ray ellipsometer equipped with six drive shafts for measurement and three ones for alignment has been designed newly and installed to BL-11 beamline, Evaluation System for Soft X-ray Optical Elements, at SR Center, Ritsumeikan University. A result of reflection measurement carried out as a performance test, the reflection profile, peak position, and reflection width of Mo/SiO multilayer polarizer, which has been fabricated newly in this study, obtained by the ellipsometer is well agree with those of the existing reflectometer.
Imazono, Takashi; Suzuki, Yoji; Sano, Kazuo*; Koike, Masato
no journal, ,
In magnetic science such as magnetic circular dichroism measurement, core electrons are excited by polarized soft X-ray. Experimenters using polarized soft X-rays as the incident light need the information on its polarization state, so that it is useful for them to evaluate it in advance. In the energy range from 0.7 to 0.9 keV, which is in the vicinity of the absorption edges of 3 transition metals, it makes impossible to perform the polarization measurement. It is because existing polarizing elements are unusable in this energy region. In order to develop new polarizing elements and evaluate the polarization state, an apparatus for soft X-ray ellipsometry based on the rotating-analyzer method has been designed and installed to the SR Center of Ritsumeikan University. We discuss the specification and the result of the preliminary performance test of this apparatus.
Wakimoto, Shuichi; Ishii, Kenji; Ikeuchi, Kazuhiko; Kakurai, Kazuhisa; Mizuki, Junichiro; Kimura, Hiroyuki*; Noda, Yukio*; Adachi, Tadashi*; Koike, Yoji*; Fujita, Masaki*; et al.
no journal, ,
no abstracts in English
Yoshida, Masahiro; Ishii, Kenji; Jarrige, I.; Mizuki, Junichiro; Murakami, Yoichi*; Kudo, Kazutaka*; Koike, Yoji*
no journal, ,
no abstracts in English