Features of Optical Anisotropy of Terbium Iron Garnet

Abstract

Rare earth iron garnets with narrow ferromagnetic resonance linewidths, very low hysteresis losses, and excellent dielectric properties have been widely applied in microwave devices in a wide range of frequencies (1100 GHz), magnetooptical transducers and typically employed as magnetic recording media [1-1. The rare earth iron garnets which can be described by chemical unit formulaRE3Fe5O12belong to cubic system with space groupIa3̄d, whose cell contains eightRE3Fe5O12molecules and crystal lattice contains three crystallographic sites, dodecahedral site 24c{RE3+}, octahedral site 16a[Fe3+] and tetrahedral site 24d(Fe3+). The garnet in fact does not allow distortion to lower symmetry owing to its non-efficiently packed structure, which makes iron garnet structure become unstable with increasing rare earth ionic radius.