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.

Theory of spin and orbital Edelstein effects

“…XMCD measurements are often used to measure equilibrium magnetizations and current-induced spin torques resulting from the spin Hall and Edelstein effect [264], as well as spin accumulation due to the spin Hall effect [265]. Theoretical calculations also predict characteristic XMCD spectra originating from the Edelstein effect [266], but there are not many reports on the experimental observation of Edelstein signatures in XMCD spectra. Kukreja et al [267] reports on XMCD signals originating from a spin-current induced magnetization in Cu, which has been interpreted as signature of the Edelstein effect [266].…”

“…Theoretical calculations also predict characteristic XMCD spectra originating from the Edelstein effect [266], but there are not many reports on the experimental observation of Edelstein signatures in XMCD spectra. Kukreja et al [267] reports on XMCD signals originating from a spin-current induced magnetization in Cu, which has been interpreted as signature of the Edelstein effect [266].…”