Local electronic structure of interstitial hydrogen in MgH inferred from muon study

Kadono, Ryosuke*; Hiraishi, Masatoshi*; Okabe, Hirotaka*; Koda, Akihiro*; Ito, Takashi

Journal of Physics; Condensed Matter, 35(28), p.285503_1 - 285503_13, 2023/07

https://doi.org/10.1088/1361-648X/acccc7

Quantum dynamics of hydrogen in the iron-based superconductor LaFeAsOD measured with inelastic neutron spectroscopy

Yamaura, 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

AA2019-0126.pdf:0.9MB

https://doi.org/10.1103/PhysRevB.99.220505

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.

J-PARC decay muon channel construction status

Strasser, P.*; Shimomura, Koichiro*; Koda, Akihiro*; Kawamura, Naritoshi*; Fujimori, Hiroshi*; Makimura, Shunsuke*; Kobayashi, Yasuo*; Nakahara, Kazutaka*; Kato, Mineo*; Takeshita, Soshi*; et al.

Journal of Physics; Conference Series, 225, p.012050_1 - 012050_8, 2010/06

https://doi.org/10.1088/1742-6596/225/1/012050