Impurity-induced tuning of quantum well states in spin-dependent resonant tunneling

TL;DR

This paper presents exact model calculations showing how impurities in quantum wells of spin-dependent resonant tunneling devices can selectively tune spin channels, significantly affecting magnetoresistance, polarization, and current.

Contribution

It introduces a novel understanding of impurity effects on quantum well states, enabling control over spin transport phenomena in magnetic tunnel junctions.

Findings

Impurities can enhance or suppress tunneling magnetoresistance.

Impurity position and potential critically influence quantum well state shifts.

Transport properties are highly sensitive to impurity-induced changes.

Abstract

We report exact model calculations of the spin-dependent tunneling in double magnetic tunnel junctions in the presence of impurities in the well. We show that the impurity can tune selectively the spin channels giving rise to a wide variety of interesting and novel transport phenomena. The tunneling magnetoresistance, the spin polarization and the local current can be dramatically enhanced or suppressed by impurities. The underlying mechanism is the impurity-induced shift of the quantum well states (QWS) which depends on the impurity potential, impurity position and the symmetry of the QWS.