$\mathit{Ab\!-\!initio}$ Determination of Magnetic Interface Coupling Constants for Magnetic Multilayers

Abstract

The magnetic (in-plane) interface coupling energy of an Au (100) /FeAu3 Fe /Au(100) multilayer system has been calculated using the well-known fully relativistic spin-polarized Screened KKR method. The coupling energy was expanded in polynomials of cos(&) in or- der to compare it with calculations using the Force Theorem method prescription. The second order term in the polynomial expansion is important when looking at total energy differences. The intention of this paper is to show the numerical feasibility of using the force theorem on particular model systems. In another paper we apply it to existing physical systems. The discovery of the oscillatory behavior of magnetic interface interactions especially in the asymptotic limit has been the subject of several studies iii. In these papers the problem of interface magnetism (I.e., the question of the so-called in-plane magnetic interface coupling energy of magnetic multilayer systems) is dealt with extensively. Suppose such a multilayer system consists of two monolayers of Fe, separated by m layers of a non-magnetic spacer, and is sandwiched semi-infinitely by the spacer material. By considering only in-plane orientations of the magnetization in the two Fe planes, only the relative angle of these two orientations should matter. The magnetic interface coupling energy,