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arXiv · 0902.0975

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

S. Nandi·A. Kreyssig·Y. Lee·Yogesh Singh·J. W. Kim·D. C. Johnston·B. N. Harmon·A. I. Goldman
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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.

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S. Nandi, A. Kreyssig, Y. Lee, Yogesh Singh, J. W. Kim, D. C. Johnston, B. N. Harmon, A. I. Goldman. 2009-02-05. Magnetic ordering in EuRh2As2 studied by x-ray resonant magnetic scattering. https://doi.org/10.1103/physrevb.79.100407

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