Electronic structures of ferromagnetic superconductors UGe
and UCoGe studied by angle-resolved photoelectron spectroscopy
角度分解光電子分光によるUGe
とUCoGeの電子状態
藤森 伸一
; 大河内 拓雄*; 川崎 郁斗*
; 保井 晃*; 竹田 幸治
; 岡根 哲夫
; 斎藤 祐児
; 藤森 淳; 山上 浩志; 芳賀 芳範
; 山本 悦嗣
; 大貫 惇睦
Fujimori, Shinichi; Okochi, Takuo*; kawasaki, Ikuto*; Yasui, Akira*; Takeda, Yukiharu; Okane, Tetsuo; Saito, Yuji; Fujimori, Atsushi; Yamagami, Hiroshi; Haga, Yoshinori; Yamamoto, Etsuji; Onuki, Yoshichika
軟X線角度分解光電子分光によってUGe
とCoGeの電子構造を明らかにした。結果をバンド計算と比較し、f電子が遍歴的な性質を持つことを明らかにした。
The electronic structures of the ferromagnetic superconductors UGe
and UCoGe in the paramagnetic phase were studied by angle-resolved photoelectron spectroscopy using soft X-rays (
= 400-500 eV). The quasi-particle bands with large contributions from U 5
states were observed in the vicinity of EF, suggesting that the U 5
electrons of these compounds have an itinerant character. Their overall band structures were explained by the band-structure calculations treating all the U 5
electrons as being itinerant. Meanwhile, the states in the vicinity of EF show considerable deviations from the results of band-structure calculations, suggesting that the shapes of Fermi surface of these compounds are qualitatively different from the calculations, possibly caused by electron correlation effect in the complicated band structures of the low-symmetry crystals. Strong hybridization between U 5
and
states in UCoGe were found by the
2p-3d resonant photoemission experiment, suggesting that
states have finite contributions to the magnetic, transport, and superconducting properties.