Magnetic and structural properties of epitaxial and polycrystalline GdIG films prepared by rf sputtering

Abstract

Magnetic, magneto-optical, and structural properties of rf-sputtered gadolinium iron garnet films are presented. The dependence of the Faraday rotation on film structure is explored and the behavior of coercivity and hysteresis loop characteristics with temperature discussed in some detail. The coercive force was found to be independent of structural differences in the various films as monitored by x-ray and electron diffraction techniques. The high coercivities observed are attributed in part to a strain induced magnetoelastic interaction. Hysteresis loops with squareness ratios of M r/Ms=1 are obtained from (111)-oriented films on (111) YAG substrates. Domain patterns are highly temperature stable in the epitaxial films. There is no evidence from magnetic and structural properties in these epitaxially grown films that cation diffusion from substrate to film is involved at crystallization temperatures below about 900°C. The films are considered quite adequate for magneto-optic memory applications. © 1971 The American Institute of Physics.