Influence of band structure effects on domain-wall resistance in diluted ferromagnetic semiconductors

TL;DR

This paper investigates how band structure effects influence domain-wall resistance in (Ga,Mn)As, combining theoretical modeling with experimental comparison to understand the impact of crystallography and magnetization profiles.

Contribution

It introduces a detailed model of spin transport in diluted ferromagnetic semiconductors that accounts for band structure effects, improving upon previous simplified models.

Findings

Band structure effects significantly affect DWR estimates.

The spherical 4x4 kp model overestimates DWR in the adiabatic limit.

DWR depends on magnetization profile and crystallographic orientation.

Abstract

Intrinsic domain-wall resistance (DWR) in (Ga,Mn)As is studied theoretically and compared to experimental results. The recently developed model of spin transport in diluted ferromagnetic semiconductors [Van Dorpe et al., Phys. Rev. B 72, 205322 (2005)] is employed. The model combines the disorder-free Landauer-B\"uttiker formalism with the tight-binding description of the host band structure. The obtained results show how much the spherical 4x4 kp model [Nguyen, Shchelushkin, and Brataas, cond-mat/0601436] overestimates DWR in the adiabatic limit, and reveal the dependence of DWR on the magnetization profile and crystallographic orientation of the wall.