Neutron Scattering Study of the Amorphous Fe₇₀Cr₁₀P₁₃C₇ Alloy

Abstract

The spin wave excitation has been studied by both inelastic neutron scattering and magnetization measurement for the amorphous Fe 70 Cr 10 P 13 C 7 alloy which almost does not exhibit the invar properties. Well defined magnon groups have been detected around (0, 0, 0) at up to q =0.1 6 Å -1 for various temperatures below T ≤0.9 T c . The spin wave stiffness constant D s has been determined to be D s =60±2 meVÅ 2 by neutron scattering which is nearly in agreement with the value D m =54±2 meVÅ 2 derived by the magnetization measurement. The spin wave linewidth \(\varGamma\) varies with both wave vector q and temperature T as \(\varGamma{\propto}q^{4}T^{2}\) as predicted for the two-magnon interaction in the Heisenberg system.