Features of optical anisotropy of europium and terbium iron garnets

Abstract The results of investigation of magnetic linear birefringence (MLB) and magnetic linear dichroism of Tb 3 Fe 5 O 12 (TbIG) iron garnet (IG) on 7 F 6 – 7 F 0 and 7 F 6 – 7 F 1 optical transitions and Eu 3 Fe 5 O 12 (EuIG) iron garnet on 7 F 0 – 7 F 6 at the variation of the directions of the magnetization vector I relative to the electric vector E linearly polarized light that propagates through single crystal iron garnets are presented. The measurements were made on Tb 3 Fe 5 О 12 and Eu 3 Fe 5 O 12 single-crystal samples in the form of plates 100 μm thick cut in the (1 1 0) and (1 0 0) plane a temperature of T = 82 K and in a magnetic field H = 22 kOe. The absorption spectra of the linearly polarized light were studied. It is shown that MLB and dichroism in the region of the 7 F 6 – 7 F 0 and 7 F 0 – 7 F 6 absorption bands reach values 10 −3 . The nonreciprocity of MLB spectra and dichroism with the change of the relative orientation of the magnetization vector I and the light wave vector is first experimentally discovered. This effect may be used as a base for the design of the different transducers such as a magnetooptical optical channels commutator.