Sensitivity of the MnTe valence band to orientation of magnetic moments

TL;DR

This paper models the MnTe valence band near the A-point and shows how its electronic structure is highly sensitive to the orientation of magnetic moments, with potential experimental implications.

Contribution

It introduces an effective model demonstrating the strong dependence of MnTe's valence band splitting on magnetic moment orientation.

Findings

Out-of-plane magnetic moments significantly increase band splitting.

Band splitting can reach about 0.5 eV with magnetic reorientation.

Proposes experimental verification of band sensitivity to magnetic order.

Abstract

An effective model of the hexagonal (NiAs-structure) manganese telluride valence band in the vicinity of the A-point of the Brillouin zone is derived. It is shown that while for the usual antiferromagnetic order (magnetic moments in the basal plane) band splitting at A is small, their out-of-plane rotation enhances the splitting dramatically (to about 0.5 eV). We propose extensions of recent experiments (Moseley et al., Phys. Rev. Materials 6, 014404) where such inversion of magnetocrystalline anisotropy has been observed in Li-doped MnTe, to confirm this unusual sensitivity of a semiconductor band structure to magnetic order.