Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
dynamics in the H conductors LaH
O
Tamatsukuri, Hiromu; Fukui, Keiga*; Iimura, Soshi*; Honda, Takashi*; Tada, Tomofumi*; Murakami, Yoichi*; Yamaura, Junichi*; Kuramoto, Yoshio*; Sagayama, Hajime*; Yamada, Takeshi*; et al.
Physical Review B, 107(18), p.184114_1 - 184114_8, 2023/05
Times Cited Count：0 Percentile：0(Materials Science, Multidisciplinary)
C; Inelastic neutron scattering studyTamatsukuri, Hiromu; Murakami, Yoichi*; Kuramoto, Yoshio*; Sagayama, Hajime*; Matsuura, Masato*; Kawakita, Yukinobu; Matsuishi, Satoru*; Washio, Yasuhito*; Inoshita, Takeshi*; Hamada, Noriaki*; et al.
Physical Review B, 102(22), p.224406_1 - 224406_5, 2020/12
Times Cited Count：8 Percentile：49.08(Materials Science, Multidisciplinary)
D
measured with inelastic neutron spectroscopyYamaura, Junichi*; Hiraka, Haruhiro*; Iimura, Soshi*; Muraba, Yoshinori*; Bang, J.*; Ikeuchi, Kazuhiko*; Nakamura, Mitsutaka; Inamura, Yasuhiro; Honda, Takashi*; Hiraishi, Masatoshi*; et al.
Physical Review B, 99(22), p.220505_1 - 220505_6, 2019/06
Times Cited Count：3 Percentile：16.31(Materials Science, Multidisciplinary)Inelastic neutron scattering was performed for an iron-based superconductor, where most of D (deuterium) replaces oxygen, while a tiny amount goes into interstitial sites. By first-principle calculation, we characterize the interstitial sites for D (and for H slightly mixed) with four equivalent potential minima. Below the superconducting transition temperature Tc = 26 K, new excitations emerge in the range 5-15 meV, while they are absent in the reference system LaFeAsOF. The strong excitations at 14.5 meV and 11.1 meV broaden rapidly around 15 K and 20 K, respectively, where each energy becomes comparable to twice of the superconducting gap. The strong excitations are ascribed to a quantum rattling, or a band motion of hydrogen, which arises only if the number of potential minima is larger than two.
DTamatsukuri, Hiromu*; Hiraka, Haruhiro*; Ikeuchi, Kazuhiko*; Iimura, Soshi*; Muraba, Yoshinori*; Nakamura, Mitsutaka; Sagayama, Hajime*; Yamaura, Junichi*; Murakami, Yoichi*; Kuramoto, Yoshio*; et al.
Physical Review B, 98(17), p.174415_1 - 174415_6, 2018/11
Times Cited Count：3 Percentile：15.56(Materials Science, Multidisciplinary)Magnetic excitations in a heavily electron-doped antiferromagnet, LaFeAsOD, have been investigated using powder inelastic neutron scattering. Unlike other parent compounds of the iron-based superconductors, the magnetic excitation gap in LaFeAsOD was not detected down to the lowest measured temperature of 4 K. This result can be understood as a result of quasi-isotropy within the ab plane, which is consistent with the band calculation result that the 
orbital plays the dominant role in the magnetism of LaFeAsOH. In addition, the intensities of the magnetic excitations in this phase are much stronger than those in nondoped LaFeAsO. Even in the paramagnetic phase, the magnetic excitation in LaFeAsOD persists. These results corroborate recent studies showing that the electron doping enhances the localized nature in this system.
Hiraishi, Masatoshi*; Iimura, Soshi*; Kojima, Kenji*; Yamaura, Junichi*; Hiraka, Haruhiro*; Ikeda, Kazutaka*; Miao, P.*; Ishikawa, Yoshihisa*; Torii, Shuki*; Miyazaki, Masanori*; et al.
Nature Physics, 10(4), p.300 - 303, 2014/04
Times Cited Count：103 Percentile：95.46(Physics, Multidisciplinary)Park, S.-W.*; Mizoguchi, Hiroshi*; Kodama, Katsuaki; Shamoto, Shinichi; Otomo, Toshiya*; Matsuishi, Satoru*; Kamiya, Toshio*; Hosono, Hideo*
Inorganic Chemistry, 52(23), p.13363 - 13368, 2013/12
Times Cited Count：33 Percentile：82.03(Chemistry, Inorganic & Nuclear)Iimura, Soshi*; Matsuishi, Satoru*; Miyakawa, Masashi*; Taniguchi, Takashi*; Suzuki, Katsuhiro*; Usui, Hidetomo*; Kuroki, Kazuhiko*; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Inamura, Yasuhiro; et al.
Physical Review B, 88(6), p.060501_1 - 060501_5, 2013/08
Times Cited Count：26 Percentile：71.33(Materials Science, Multidisciplinary)Hanna, Taku*; Matsuishi, Satoru*; Kodama, Katsuaki; Otomo, Toshiya*; Shamoto, Shinichi; Hosono, Hideo*
Physical Review B, 87(2), p.020401_1 - 020401_5, 2013/01
Times Cited Count：35 Percentile：78.6(Materials Science, Multidisciplinary)
HMatsuishi, Satoru*; Hanna, Taku*; Muraba, Yoshinori*; Kim, S. W.*; Kim, J. E.*; Takata, Masaki*; Shamoto, Shinichi; Smith, R. I.*; Hosono, Hideo*
Physical Review B, 85(1), p.014514_1 - 014514_6, 2012/01
Times Cited Count：46 Percentile：84.61(Materials Science, Multidisciplinary)We performed the neutron powder diffraction and synchrotron X-ray diffraction measurements on CeFeAsO(D,H) (
= 0.0-0.48) as a representative of 1111-type family of iron-based superconductors LnFeAsOH (
= lanthanoid). These results strongly suggest that H ions exclusively occupy the oxygen sites in both samples, regardless of the hydrogen species in the starting material.
Hanna, Taku*; Muraba, Yoshinori*; Matsuishi, Satoru*; Igawa, Naoki; Kodama, Katsuaki; Shamoto, Shinichi; Hosono, Hideo*
Physical Review B, 84(2), p.024521_1 - 024521_7, 2011/07
Times Cited Count：102 Percentile：94.65(Materials Science, Multidisciplinary)
Bi
Kodama, Katsuaki; Wakimoto, Shuichi; Igawa, Naoki; Shamoto, Shinichi; Mizoguchi, Hiroshi*; Hosono, Hideo*
Physical Review B, 83(21), p.214512_1 - 214512_5, 2011/06
Times Cited Count：19 Percentile：61.3(Materials Science, Multidisciplinary)Yanagi, Hiroshi*; Watanabe, Takumi*; Kodama, Katsuaki; Iikubo, Satoshi*; Shamoto, Shinichi; Kamiya, Toshio*; Hirano, Masahiro*; Hosono, Hideo*
Journal of Applied Physics, 105(9), p.093916_1 - 093916_8, 2009/05
Times Cited Count：47 Percentile：83.35(Physics, Applied)Electronic and magnetic properties of a layered compound LaMnPO are examined in relation to a newly discovered iso-structural superconductor LaFeAs(P)O. Neutron diffraction measurements, together with temperature dependent magnetic susceptibility, clarify that LaMnPO is an antiferromagnet at least up to 375 K. The spin moment of a Mn ion is determined to be 2.26 
at room temperature, and the spin configuration is antiparallel in the Mn-P plane and parallel to between the Mn-P planes, which is rather different from that of LaFeAsO. Optical absorption spectra, photoemission spectra, and temperature dependent electrical conductivity indicate that LaMnPO is a semiconductor. Furthermore, nominally undoped LaMnPO exhibits 
-type conduction while the conduction type is changed by doping of Cu or Ca to the La sites, indicating that LaMnPO is a bipolar conductor. Density functional calculation using the GGA+U approximation supports the above conclusions; the electronic band structure has an open band gap and the antiferromagnetic spin configuration is more stable than the ferromagnetic one.
Ishikado, Motoyuki; Kajimoto, Ryoichi; Shamoto, Shinichi; Arai, Masatoshi; Iyo, Akira*; Miyazawa, Kiichi*; Shirage, P. M.*; Kito, Hijiri*; Eisaki, Hiroshi*; Kim, S.-W.*; et al.
Journal of the Physical Society of Japan, 78(4), p.043705_1 - 043705_4, 2009/04
Times Cited Count：34 Percentile：80.55(Physics, Multidisciplinary)F
and PrFeAsO
via inelastic X-ray scattering and first-principles calculationFukuda, Tatsuo; Baron, A. Q. R.*; Shamoto, Shinichi; Ishikado, Motoyuki; Nakamura, Hiroki; Machida, Masahiko; Uchiyama, Hiroshi*; Tsutsui, Satoshi*; Iyo, Akira*; Kito, Hijiri*; et al.
Journal of the Physical Society of Japan, 77(10), p.103715_1 - 103715_4, 2008/10
Times Cited Count：42 Percentile：83.23(Physics, Multidisciplinary)The lattice dynamics of LaFeAsOF (=0, 0.1) and PrFeAsO (
0.1) are investigated using inelastic X-ray scattering. Measurements of powder samples provide an approximation to the phonon DOS, while dispersion is measured from a single crystal of PrFeAsO. A model that agrees reasonably well with all of the data at room temperature is built from results of ab-initio calculations by reducing the strength of the Fe-As bond by 30%.
Koizumi, Norikiyo; Okuno, Kiyoshi; Takahashi, Yoshikazu; Tsuji, Hiroshi; Nishi, Masataka; Sugimoto, Makoto; Isono, Takaaki; Sasaki, Takashi*; Hiue, Hisaaki*; Yasukawa, Yukio*; et al.
Teion Kogaku, 28(3), p.150 - 159, 1993/00
no abstracts in English
F and PrFeAsO via inelastic X-ray scatteringFukuda, Tatsuo; Baron, A. Q. R.*; Shamoto, Shinichi; Ishikado, Motoyuki; Nakamura, Hiroki; Machida, Masahiko; Uchiyama, Hiroshi*; Tsutsui, Satoshi*; Iyo, Akira*; Kito, Hijiri*; et al.
no journal, ,
We studied the lattice dynamics of powders, LaFeAsOF (=0, 0.1) and PrFeAsO (0.4), and a single crystal, PrFeAsO (0.1), using inelastic X-ray scattering. The third peak in phonon density of states are found to be softened by 5 meV compared with ab-initio calculations. A model that agrees reasonably well with all of the data is built from results of ab-initio calculations by reducing the strength of the Fe-As bond by 30%.
Ishikado, Motoyuki; Kajimoto, Ryoichi; Shamoto, Shinichi; Arai, Masatoshi; Iyo, Akira*; Miyazawa, Kiichi*; Shirage, P. M.*; Kito, Hijiri*; Eisaki, Hiroshi*; Kim, S.*; et al.
no journal, ,
no abstracts in English
Ishikado, Motoyuki; Kajimoto, Ryoichi; Shamoto, Shinichi; Arai, Masatoshi; Iyo, Akira*; Miyazawa, Kiichi*; Shirage, P. M.*; Kito, Hijiri*; Eisaki, Hiroshi*; Kim, S.-W.*; et al.
no journal, ,
no abstracts in English
Ishikado, Motoyuki; Kajimoto, Ryoichi; Shamoto, Shinichi; Arai, Masatoshi; Iyo, Akira*; Miyazawa, Kiichi*; Shirage, P. M.*; Kito, Hijiri*; Eisaki, Hiroshi*; Kim, S.-W.*; et al.
no journal, ,
The parent compound of Fe oxypnictide superconductor, LaFeAsO, has been studied by pulsed neutron powder inelastic scattering measurement. The inelastic scattering intensity along Q-axis at T = 140 K exhibits a prominent asymmetric peak ascribed to (
, , 
) magnetic rod, suggesting the two-dimensionality of the spin density wave.
Ishikado, Motoyuki; Kajimoto, Ryoichi; Shamoto, Shinichi; Arai, Masatoshi; Iyo, Akira*; Miyazawa, Kiichi*; Shirage, P. M.*; Kito, Hijiri*; Eisaki, Hiroshi*; Kim, S.-W.*; et al.
no journal, ,
The parent compound of Fe oxypnictide superconductor, LaFeAsO, has been studied by pulsed neutron powder inelastic scattering measurement. The inelastic scattering intensity along Q-axis at T=140 K exhibits prominent asymmetric peaks ascribed to the magnetic rod, suggesting the two-dimensionality of the spin density wave above the magnetic transition temperature. It persists even in the tetragonal phase up to room temperature.
