Short-range magnetic order in a spin density wave in Cr-based multilayers

A mechanism of the formation of the short antiferromagnetic order with a sp in density wave (SDW) in the vicinity of the interfaces in the Fe/Cr type m ultilayers is proposed. The main reason behind the emergence of magnetic or dering with SDWs is the redistribution of charge (and, hence, spin) density in the vicinity of Fe/Cr interfaces, which leads to the paramagnetic phase instability at a temperature considerably higher than the Neel temperature in chromium. The Ginzburg-Landau expansion for the free energy of the syst em is used for determining the inhomogeneous collinear structures of CDWs a nd for constructing the phase diagram (the dependence of the transition tem perature on the thickness of the antiferromagnetic interlayer). The obtaine d results are used for discussing the experimental data on neutron scatteri ng and tunnel microscopy. (C) 2001 MAIK "Nauka/Interperiodica".