Symmetry analysis of magneto-optical effects: The case of x-ray diffraction and x-ray absorption at the transition metal L23 edge

TL;DR

This paper develops a symmetry-based formalism to analyze magneto-optical effects in x-ray diffraction and absorption, revealing significant deviations from spherical symmetry that impact the interpretation of experimental data.

Contribution

It introduces a general symmetry analysis framework for the optical conductivity tensor, applied to transition metal L23 edges, highlighting deviations from spherical symmetry in magneto-optical effects.

Findings

Large deviations from spherical symmetry in magneto-optical effects.

Implications for interpreting polarization and azimuthal dependence in x-ray diffraction.

Enhanced understanding of local magnetization orientation determination.

Abstract

A general symmetry analysis of the optical conductivity or scattering tensor is used to rewrite the conductivity tensor as a sum of fundamental spectra multiplied by simple functions depending on the local magnetization direction. Using this formalism, we present several numerical examples at the transition metal L23 edge. From these numerical calculations we can conclude that large deviations from the magneto-optical effects in spherical symmetry are found. These findings are in particular important for resonant x-ray diffraction experiments where the polarization dependence and azimuthal dependence of the scattered Bragg intensity is used to determine the local ordered magnetization direction.