Structural distortion stabilizing the antiferromagnetic and semiconducting ground state of BaMn2As2

Abstract

We report evidence that the experimentally found antiferromagnetic structure as well as the semiconducting ground state of BaMn2As2 are caused by optimally-localized Wannier states of special symmetry existing at the Fermi level of BaMn2As2. In addition, we find that a (small) tetragonal distortion of the crystal is required to stabilize the antiferromagnetic semiconducting state. To our knowledge, this distortion has not yet been established experimentally.