Magnetic properties of Bi-doped GdCrO

Yoshii, Kenji  ; Tsuji, Takuya  ; Matsumura, Daiju   ; Nishida, Ginichi*; Inoue, Naoki*; Fukada, Yukimasa*; Yaita, Tsuyoshi

We have investigated the magnetic properties of Bi-doped perovskite GdCrO, which was reported to be multiferroic below the magnetic transition temperature (170 K). For the low doping levels (about 5-10% Bi at the Gd site), single-phase samples could be prepared at 920C, a temperature which is much lower than the firing temperature of GdCrO (about 1300-1400C). This result is essentially the same as that of isostructural (Sm,Bi)CrO. Magnetic measurements showed that the magnetic properties were essentially identical to those of GdCrO. For example, the chromium spins show a ferrimagnetic transition at 170 K. Interestingly, these properties were entirely different from those of (Sm,Bi)CrO, which showed that the Bi doping led to a drastic lowering of magnetic transition temperature (by 140 K). We have also conducted X-ray absorption measurements to determine the crystallographic site of Bi. The results will be shown at the conference.