Giant widening of interface magnetic layer in almost compensated iron garnet

Y. B. Kudasov; M. V. Logunov; R. V. Kozabaranov; I. V. Makarov; V. V. Platonov; O. M. Surdin; D. A. Maslov; A. S. Korshunov; I. S. Strelkov; A. I. Stognij; V. D. Selemir; S. A. Nikitov

doi:10.1063/5.0086067

paper

Giant widening of interface magnetic layer in almost compensated iron garnet

arXiv:2201.00134 · doi:10.1063/5.0086067

Abstract

A two-sublattice ferrimagnet undergoes a transition from a collinear to canted magnetic phase at magnetic field oriented along an easy magnetization direction. In this work, we study the transition by means of the magneto-optical Faraday effect in a thin film of compensated iron garnet (Lu $_{3 - x}$ Bi $_{x}$ )(Fe $_{5 - y - z}$ Ga $_{y}$ Al $_{z}$ )O $_{12}$ grown on Gd $_{3}$ Ga $_{5}$ O $_{12}$ substrate. In the immediate vicinity of the compensation temperature a precursor of the transition with a complex shape was observed. Using a special sample with variable thickness we demonstrate an interfacial origin of the precursor. Diffusion of gadolinium from the substrate into the film forms a thin intermixed layer with enhanced magnetization. It induces an extended inhomogeneous magnetic structure in the film. A two-step shape of the precursor appears due to an easy-plane anisotropy of the intermixed magnetic layer. We emphasize that an effective width of the inhomogeneous magnetization distribution in the film grows enormously while approaching the compensation temperature.

10 pages, 5 figures