Valence band structure of YbRhSi studied by soft X-ray angle-resolved photoemission spectroscopy

Yasui, Akira; Fujimori, Shinichi   ; Kawasaki, Ikuto  ; Okane, Tetsuo  ; Takeda, Yukiharu   ; Saito, Yuji  ; Lapertot, G.*; Knebel, G.*; Matsuda, Tatsuma; Haga, Yoshinori   ; Yamagami, Hiroshi

In recent years, YbRhSi has been attracted much attention because it can be turned through a quantum critical point (QCP) by various small changes of control parameters. Many studies on its electronic structure have been performed for this compound to understand the nature of the QCP, but its bulk electronic structure has not been understood. Experimental observations of the valence-band structure including Yb 4 bands are needed to establish the theoretical model which describes the electronic structure of YbRhSi correctly. We have performed the soft X-ray angle-resolved photoemission spectroscopy for YbRhSi to obtain its bulk valence-band structure. Experimental valence-band structure is similar to the calculated result of LuRhSi within a local-density approximation, while the Yb 4 bands are observed near Fermi level.