Spin transport theory in ferromagnet/semiconductor systems with non-collinear magnetization configurations

TL;DR

This paper develops a comprehensive theory for spin transport in semiconductor systems with non-collinear ferromagnetic contacts, incorporating non-linear I-V relations and non-coherent mechanisms, and demonstrates its application to a three-terminal structure.

Contribution

It introduces a generalized spin transport model for non-collinear configurations, extending the Landauer-Büttiker approach with non-linear and non-coherent effects.

Findings

Significant differences in spin accumulation profiles compared to conventional models.

The generalized theory accurately describes spin dynamics in complex ferromagnet/semiconductor systems.

Application to a three-terminal device highlights the importance of non-linear and non-coherent effects.

Abstract

We present a comprehensive theory of spin transport in a non-degenerate semiconductor that is in contact with multiple ferromagnetic terminals. The spin dynamics in the semiconductor is studied during a perturbation of a general, non-collinear magnetization configuration and a method is shown to identify the various configurations from current signals. The conventional Landauer-B\"{u}ttiker description for spin transport across Schottky contacts is generalized by the use of a non-linearized I-V relation, and it is extended by taking into account non-coherent transport mechanisms. The theory is used to analyze a three terminal lateral structure where a significant difference in the spin accumulation profile is found when comparing the results of this model with the conventional model.