Noncollinear magnetic states in iron-chromium-type multilayers

A model of noncollinear magnetic ordering in Fe/Cr-type multistructures was suggested. The model was based on the idea of charge (and, as a consequence, spin) density redistribution near a metal-metal interface. A peculiar state of the whole structure characterized by strong short-range antiferromagnetic ordering in the interlayer and a pronounced dependence of magnetic characteristics on the properties of the boundary between iron and chromium layers was shown to be formed in a certain temperature range. Inhomogeneous antiferromagnetic structures with a vector order parameter were found, and the effective exchange coupling between neighboring iron layer moments was calculated using the Ginzburg-Landau expansion of the thermodynamic potential. The results were used to discuss the experimental data on Fe/Cr superlattices obtained in neutron scattering and magnetization measurements.