Multiscale approach to spin transport in magnetic multilayers

TL;DR

This paper presents a multiscale framework combining quantum and semiclassical models to accurately simulate spin transport in magnetic multilayers across different physical scales.

Contribution

It introduces a systematic method integrating Tight-Binding and Continuous Random Matrix Theory approaches for multiscale spin transport simulations.

Findings

CRMT and TB models produce consistent results within their overlapping domain.

The combined approach captures physics at multiple relevant scales.

The method enables more accurate modeling of spin phenomena in multilayer structures.

Abstract

This article discusses two dual approaches to spin transport in magnetic multilayers: a direct, purely quantum, approach based on a Tight-Biding model (TB) and a semiclassical approach (Continuous Random Matrix Theory, CRMT). The combination of both approaches provides a systematic way to perform multi-scales simulations of systems that contain relevant physics at scales larger (spin accumulation, spin diffusion...) and smaller (specular reflexions, tunneling...) than the elastic mean free paths of the layers. We show explicitly that CRMT and TB give consistent results in their common domain of applicability.