Spin extraction theory and its relevance to spintronics

TL;DR

This paper develops a scattering theory for electron spin extraction and injection at semiconductor-ferromagnet interfaces, emphasizing the role of interface bound states, and demonstrates its relevance to spintronic devices like spin switches.

Contribution

It introduces a comprehensive scattering theory that accounts for interface bound states, explaining recent experimental results and advancing understanding in spintronics.

Findings

Interface bound states significantly affect spin extraction.

The theory explains contradictory experimental spin imaging results.

Application to spin switches demonstrates practical relevance.

Abstract

Extraction of electrons from a semiconductor to a ferromagnet as well as the case of injection in the reverse direction may be formulated as a scattering theory. However, the presence of bound states at the interface arising out of doping on the semiconductor side must be taken into account in the scattering theory. Inclusion of the interface states yields an explanation of a recent result of spin imaging measurement which contradicts the current understanding of spin extraction. The importance of an extraction theory to spintronics is illustrated by an application to a spin switch.