Element specific electronic states and spin-flip-like behavior of Ce in (CeGd)Ni composed of heavy fermion CeNi and ferri-magnet GdNi through XMCD method

Yano, Kazuo*; Okane, Tetsuo  ; Takeda, Yukiharu   ; Yamagami, Hiroshi; Fujimori, Atsushi; Nishimura, Katsuhiko*; Sato, Kiyoo*

The electronic states of the three constituent elements in the crystal mixed system between CeNi and GdNi, CeGdNi, were investigated by soft X-ray magnetic circular dichroism (XMCD). Not only Gd 4f but also Ni 3d and Ce 4f electrons were magnetic and both magnetic moments of Ni and Ce were coupled anti-parallel to the direction of the Gd magnetic moment. After saturation, Ce magnetic moment decreased over 2 T and this behavior was explained by a spin-flip behavior of the Ce magnetic moment. In addition, sum rule analysis has revealed that the magnetic moments of Gd 4 f and Ni 3d electrons could retain small values of orbital magnetic moments.