Electronic structure of URuSi studied by photoelectron spectroscopy (INVITED)

Fujimori, Shinichi   ; Takeda, Yukiharu   ; Okane, Tetsuo  ; Saito, Yuji  ; Fujimori, Atsushi; Yamagami, Hiroshi; Haga, Yoshinori   ; Yamamoto, Etsuji  ; Onuki, Yoshichika*

One of the most remarkable properties of actinide compounds is the coexistence of superconductivity and magnetic ordering which has been realized in several strongly-correlated uranium based compounds. In these compounds, both superconductivity and magnetic ordering originate from U 5f states. To understand the origin of the coexistence as well as the mechanism of the superconductivity, it is essential to reveal their U 5f electronic structures. In this presentation, the U 5f electronic structures of heavy Fermion superconductors UPdAl and URuSi studied by photoelectron spectroscopy using soft X-rays from SPring-8 BL23SU are presented. For UPdAl, U 4d-5f resonant photoemission experiment was performed, and its partial U 5f spectrum was revealed experimentally. Furthermore, we have applied the three-dimentional ARPES to the hidden order compound URuSi, and revealed its complete 3D electronic structure in the paramagnetic phase. Their electronic structures are discussed based on these results.