文档介绍：Ab Initio Theory of the Interlayer Exchange
Coupling
J. Kudrnovsk´y1,2, V. Drchal1,2, I. Turek3,2, P. Bruno4, P. Dederichs5, and P.
Weinberger2
1 Institute of Physics, Academy of Sciences of the Czech Republic, CZ-182 21 Praha
8, Czech Republic
2 Center putational Materials Science, Technical University, A-1060 Vienna,
Austria
3 Institute of Physics of Materials, Academy of Sciences of the Czech Republic,
CZ-616 62 Brno, Czech Republic
4 Max-Planck Institut f¨ur Mikrostrukturphysik, D-06120 Halle, Germany
5 Institut f¨ur Festk¨orperforschung, Forschungszentrum J¨ulich, D-52425 J¨ulich,
Germany
Abstract. Ab initio formulations of the interlayer exchange coupling (IEC) between
two, in general non-collinearly aligned ic slabs embedded in a non-ic
spacer are reviewed whereby both the spacer and the ic slabs as well as their
interfaces may be either ideal or random. These formulations are based on the spin-
polarized surface Green function technique within the tight-binding linear muffin-tin
orbital method, the Lloyd formulation of the IEC, and the coherent potential appro-
ximation using the vertex-cancellation theorem. We also present an effective method
for the study of the temperature dependence of the IEC. The periods, amplitudes, and
phases are studied in terms of discrete Fourier transformations, the asymptotic be-
havior of the IEC is briefly discussed within the stationary-phase method. Numerical
results illustrating the theory are presented.
1 Introduction
Oscillatory interlayer exchange coupling (IEC) has been found in a number of
ic/non-ic multilayer systems and is in some cases pa-
nied by an oscillatory oresistance. The physical origin of such oscillations
is attributed to quantum interferences due to spin-dependent confinement of the
electrons in the spacer. The periods of the oscillations with respect to the spacer
thickness can be correlated to the spacer Fermi surface, a relation frequently
used i