Gd-Y-Sc合金の結晶磁気異方性

Magnetocrystalline anisotropy 'measurements have been made on a single-crystal sample of Gd_<75>Y_<17.5>Sc_<7.5> alloy over the temperature range from 77 to 240 K using a torque magnetometer. It is shown that at temperatures greater than T〓(=191K) the apparent easy direction of magnetization in the low field is c-axis. Below this temperature the easy direction lies on a basal plane. In the temperature range between T〓 and T_c ( = 219K), the anisotropy constant K_1 increase initially up to about 3kOe and then decrease with increasing field. This corresponds to the change in the apparent easy direction from c- to a-axis with increasing magnetic field, which in itself is unusual behaviour for ferromagnet.