Spin-Dependent Phenomena in (Ga,Mn)As Heterostructures

Abstract

A model for spin-dependent tunneling in semiconductor heterostructures, which combines a multi-orbital empirical tight-binding approach with a Landauer-Büttiker formalism, is presented. Using this approach we explain several phenomena observed in modulated structures of (Ga,Mn)As, i.e., large values of the electron current spin polarization in magnetic EsakiZener diode and the high tunneling magnetoresistance ratio. Next, the relevance of this theory to assess the tunneling anisotropic magnetoresistance effect is studied. The results of applying the tight-binding model to describe the recently observed interlayer exchange coupling in (Ga,Mn)As-based superlattices are also shown.