Magnetic ordering in EuRh2As2 studied by x-ray resonant magnetic scattering

TL;DR

This study uses x-ray resonant magnetic scattering to investigate the complex magnetic structures of Eu in EuRh2As2, revealing coexistence of incommensurate and commensurate antiferromagnetic phases with detailed magnetic moment orientations.

Contribution

It provides the first detailed element-specific magnetic structure analysis of EuRh2As2, showing coexistence of magnetic phases and their temperature-dependent behavior.

Findings

Coexistence of incommensurate and commensurate antiferromagnetic structures.

Magnetic moments lie in the basal plane and are ferromagnetically aligned.

Incommensurate structure is a spiral with a 162° turn angle.

Abstract

Element-specific x-ray resonant magnetic scattering investigations were performed to determine the magnetic structure of Eu in EuRh2As2. In the temperature range from 46 K down to 6 K, an incommensurate antiferromagnetic (ICM)structure with a temperature dependent propagation vector (0 0 0.9) coexists with a commensurate antiferromagnetic (CM) structure. Angular-dependent measurements of the magnetic intensity indicate that the magnetic moments lie in the tetragonal basal plane and are ferromagnetically aligned within the a-b plane for both magnetic structures. The ICM structure is a spiral-like magnetic structure with a turn angle of 162 deg between adjacent Eu planes. In the CM structure, this angle is 180 deg. These results are consistent with band-structure calculations which indicate a strong sensitivity of the magnetic configuration on the Eu valence.