Soft X-ray magnetic circular dichroism study on UGe

Takeda, Yukiharu   ; Okane, Tetsuo  ; Saito, Yuji  ; Yamagami, Hiroshi; Yamamoto, Etsuji  ; Haga, Yoshinori   

In order to investigate the electronic and magnetic states of UGe element-specifically, we have performed soft X-ray magnetic circular dichroism experiments at the U N and Ge L absorption edges. We have detected the XMCD signals at both the U and Ge sites and observed clear hysteresis loops in the ferromagnetic (FM) state at T = 5.5 K. From the branching ratio B, it is found that the occupation number of 5f electrons (n) in UGe is close to 3. In addition, applying the magneto-optical sum rules analysis to the XMCD spectrum at the U N edges, the ratio of orbital magnetic moment to the spin magnetic moment (-M/M) is estimated to be 2.17. These values of B and -M/M are comparable compared with the results of other FM superconductors: URhGe and UCoGe