Multilayers of Zinc-Blende Half-Metals with Semiconductors

TL;DR

This study uses first-principles calculations to explore multilayer structures of zinc-blende half-metallic ferromagnets with semiconductors, showing that half-metallicity can be maintained under certain structural conditions.

Contribution

It provides new insights into the stability of half-metallicity in multilayer heterostructures with semiconductors, including a rule for evaluating interface spin moments.

Findings

Half-metallicity can be preserved in multilayer heterostructures.

A mechanism for non-integer interface spin moments is described.

Structural and bonding conditions are crucial for maintaining half-metallicity.

Abstract

We report on first-principles calculations of multilayers of zinc-blende half-metallic ferromagnets CrAs and CrSb with III-V and II-VI semiconductors, in the [001] orientation. We examine the ideal and tetragonalised structures, as well as the case of an intermixed interface. We find that, as a rule, half-metallicity can be conserved throughout the heterostructures, provided that the character of the local coordination and bonding is not disturbed. At the interfaces with semiconductors, we describe a mechanism that can give also a non-integer spin moment per interface transition atom, and derive a simple rule to evaluate it.