Complete spin extraction from semiconductors near ferromagnet-semiconductor interfaces

TL;DR

This paper demonstrates that near specific ferromagnet-semiconductor interfaces, electron spin polarization can reach 100% due to electric field effects, enabling complete spin extraction even with moderate injection coefficients.

Contribution

It introduces a method for achieving complete spin polarization in semiconductors by exploiting electric field-induced reduction of spin penetration length at tailored interfaces.

Findings

Achieves 100% spin polarization near ferromagnet-semiconductor interfaces.

Complete spin extraction occurs at moderate injection coefficients.

Electric fields significantly enhance spin penetration control.

Abstract

We show that spin polarization of electrons in nonmagnetic semiconductors near specially tailored ferromagnet-semiconductor junctions can achieve 100%. This effect is realized even at moderate spin injection coefficients of the contact when these coefficients only weakly depend on the current. The effect of complete spin extraction occurs at relatively strong electric fields and arises from a reduction of spin penetration length due to the drift of electrons from a semiconductor towards the spin-selective tunnel junction.