First-principles calculations of steady-state voltage-controlled magnetism: Application to X-ray absorption spectroscopy experiments

Abstract

Recent X-ray absorption experiments have demonstrated the possibility to accurately monitor the magnetism of metallic heterostructures controlled via a time-independent perturbation caused, for example, by a static electric field. Using a first-principles, nonequilibrium Green's function scheme, we show how the measured dichroic signal for the corresponding steady-state situation can be related to the underlying electronic structure and its response to the external stimulus. The suggested approach works from the infinitesimal limit of linear response to the regime of strong electric field effects, which is realized in present experimental high-sensitivity investigations.