Electronic structure of UTe studied by photoelectron spectroscopy

光電子分光によるUTeの電子状態研究

藤森 伸一   ; 川崎 郁斗  ; 竹田 幸治   ; 山上 浩志; 仲村 愛*; 本間 佳哉*; 青木 大*

Fujimori, Shinichi; Kawasaki, Ikuto; Takeda, Yukiharu; Yamagami, Hiroshi; Nakamura, Ai*; Homma, Yoshiya*; Aoki, Dai*

The electronic structure of UTe was studied by resonant photoelectron spectroscopy (RPES) and angle-resolved photoelectron spectroscopy (ARPES) with soft X-ray synchrotron radiation. The partial U 5f density of states of UTe were imaged by the U~- RPES and it was found that the U~ state has an itinerant character, but there exists an incoherent peak due to the strong electron correlation effects. The band structure of UTe was obtained by ARPES and its overall band structure was mostly explained by band structure calculations, except for the incoherent band at eV. These results suggest that the U~ states of UTe have itinerant but strongly-correlated nature with enhanced hybridization with the Te~ states. In addition, the valence state of UTe was studied by core-level photoelectron spectroscopy. The main peak position of the U~ core-level spectrum of UTe coincides with that of UB, which is an itinerant compound with a nearly configuration. However, the main peak of UTe is broader than that of UB, and satellite structures are observed in the higher binding energy side of the main peak, which are characteristics of mixed-valence uranium compounds. These results suggest that the U~ state in UTe is in a mixed valence state with a dominant contribution from the itinerant 5 configuration.