General treatment of off-specular resonant soft x-ray magnetic scattering using the distorted-wave Born approximation: Numerical algorithm and experimental studies with hybrid chiral domain structures

We present a numerical algorithm for the simulation of resonant x-ray magnetic scattering in reflection geometry for an arbitrary three-dimensional magnetization distribution over a multilayer sample utilizing the distorted-wave Born approximation. Our approach takes the medium boundary matrix approach for specular reflection, and the Born approximation typically used for off-specular reflection, combines the two, and adds the contribution from transmission through the sample before and after a reflection event. The algorithm is then tested on experimental data from an Al2O3/Co/Pt multilayer sample with hybrid Neel/Bloch/Neel domain walls at incidence angles at and near multilayer Bragg angles, and photon energies near the Co L-3 absorption edge, achieving high levels of agreement with experimental data. Incorporating the transmission components into the algorithm was found to explain the dichroism observed in scattering from Bloch-type domain walls, and uncovered the likely importance of diffuse scattering in transmission from the polycrystalline grain walls along the optical path of the x rays in the sample-a theme which deserves further investigation.

Automated summary

This study introduces a numerical algorithm for simulating resonant x-ray magnetic scattering taking into account the magnetization distribution over a multilayer sample, achieving high agreement with experimental data. Incorporating the transmission components into the algorithm was found to be crucial for explaining the dichroism observed in scattering from Bloch-type domain walls.