High Temperature Relaxation of the Uniaxial Anisotropy of Eu_2.2 Gd_0.8 Al_0.6 Fe_4.4 O₁₂ Garnet

Abstract

Heat treatment relaxation of the growth-induced uniaxial anisotropy of the mixed garnet (Eu_2.2 Gd_0.8 Al_0.6 Fe_4.4 O₁₂) was investigated by means of annealing the specimen at high temperature in various atmospheres. The relaxation of the anisotropy constant of this garnet consists of two processes. At 1000°C, these relaxation times are 12 minutes and 35.0 hours for the two processes, respectively. It is supposed that the diffusion of rare earth ions is mediated by the oxygen vacancies.