Revising the 4 symmetry in CeCuGe; Soft X-ray absorption and hard X-ray photoemission spectroscopy

軟X線吸収分光と硬X線光電子分光によるCeCuGeの4対称性の決定

荒谷 秀和*; 中谷 泰博*; 藤原 秀紀*; 川田 萌樹*; 金井 惟奈*; 山神 光平*; 藤岡 修平*; 濱本 諭*; 久我 健太郎*; 木須 孝幸*; 山崎 篤志*; 東谷 篤志*; 門野 利治*; 今田 真*; 田中 新*; 玉作 賢治*; 矢橋 牧名*; 石川 哲也*; 保井 晃*; 斎藤 祐児  ; 鳴海 康雄*; 金道 浩一*; 海老原 孝雄*; 関山 明*

Aratani, Hidekazu*; Nakatani, Yasuhiro*; Fujiwara, Hidenori*; Kawada, Moeki*; Kanai, Yuina*; Yamagami, Kohei*; Fujioka, Shuhei*; Hamamoto, Satoru*; Kuga, Kentaro*; Kiss, Takayuki*; Yamasaki, Atsushi*; Higashiya, Atsushi*; Kadono, Toshiharu*; Imada, Shin*; Tanaka, Arata*; Tamasaku, Kenji*; Yabashi, Makina*; Ishikawa, Tetsuya*; Yasui, Akira*; Saito, Yuji; Narumi, Yasuo*; Kindo, Koichi*; Ebihara, Takao*; Sekiyama, Akira*

We present a detailed study on the ground state symmetry of the pressure-induced superconductor CeCuGe probed by soft X-ray absorption and hard X-ray photoemission spectroscopy. The revised Ce ground states are determined as with in-plane rotational symmetry. This gives an in-plane magnetic moment consistent with the antiferromagnetic moment as reported in neutron measurements. Since the in-plane symmetry is the same as that for the superconductor CeCuSi, we propose that the charge distribution along the -axis plays an essential role in driving the system into a superconducting phase.