Pair-Preference and Site-Preference Models for Rare-Earth Iron Garnets Exhibiting Noncubic Magnetic Anisotropies

Abstract

The pair anisotropy model is extended to include the next-nearest-neighbor tetrahedral-iron ions. An anisotropy model based on growth-induced preferential site occupation is derived using the pair model. With the site model the nearest-neighbor tetrahedral- and nearest-neighbor octahedral-iron ions lead solely to a uniaxial anisotropy under both growth facets. Inclusion of the next-nearest-neighbor tetrahedral-iron ions results in the experimentally observed orthorhombic anisotropies.