Ab initio typical medium theory of substitutional disorder

TL;DR

This paper introduces a combined theoretical framework merging typical medium theory with density functional theory to accurately model substitutional disorder and Anderson localization effects in materials, providing new insights into electronic and magnetic properties.

Contribution

It presents a self-consistent computational scheme that incorporates Anderson localization into electronic structure calculations for disordered materials, extending the capabilities of existing methods.

Findings

Anderson localization suppresses ferromagnetism at low impurity concentrations.

The method accurately predicts electronic structures of disordered alloys.

Comparison with coherent potential approximation shows improved results.

Abstract

By merging single-site typical medium theory with density functional theory we introduce a self-consistent framework for electronic structure calculations of materials with substitutional disorder which takes into account Anderson localization. The scheme and details of the implementation are presented and applied to the hypothetical alloy Li$_{c}$Be$_{1-c}$, and the results are compared with those obtained with the coherent potential approximation. Furthermore we demonstrate that Anderson localization suppresses ferromagnetic order for a very low concentration of (i) carbon impurities substituting oxygen in MgO$_{1-c}$C$_{c}$, and (ii) manganese impurities substituting magnesium in Mg$_{1-c}$Mn$_c$O for the low-spin magnetic configuration.