Spin wave excitation on amorphous Co(80+x)TM(12)B(8-x) alloys

Abstract

Amorphous Co(80+x)TM(12)B(8-x) (TM = Ti, Zr, Hf, Nh; x = 0, 2, 4 at%) alloys were prepared by the single-roller melt-spinning technique. The saturation magnetization of the amorphous ribbons was measured by a SQUID and a vibrating sample magnetometer at 5-800 K under an applied field of 10 kOe. Typical thermo-magnetization curves were observed, and average values of the spectroscopic splitting g factor were estimated from the ferromagnetic resonance (FMR) curve. For all the amorphous alloys studied here, the saturation magnetization in the temperature range 5 K up to about 0.3T(C) can be described by the Bloch relation, M(s)(T) = M(s)(0)(1 - BT3/2 - CT5/2). The spin wave stiffness constants were calculated from the values of M(s)(0), B and the spectroscopic splitting g factor.