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arXiv · 2305.07653

Resonant elastic X-ray scattering of antiferromagnetic superstructures in EuPtSi$_{3}$

Wolfgang Simeth·Andreas Bauer·Christian Franz·Aisha Aqeel·Pablo J. Bereciartua Perez·Jennifer A. Sears·Sonia Francoual·Christian H. Back·Christian Pfleiderer
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Abstract

We report resonant elastic X-ray scattering (REXS) of long-range magnetic order in EuPtSi$_{\text{3}}$, combining different scattering geometries with full linear polarization analysis to unambiguously identify magnetic scattering contributions. At low temperatures, EuPtSi$_{\text{3}}$ stabilizes type A antiferromagnetism featuring various long-wavelength modulations. For magnetic fields applied in the hard magnetic basal plane, well-defined regimes of cycloidal, conical, and fan-like superstructures may be distinguished that encompass a pocket of commensurate type A order without superstructure. For magnetic field applied along the easy axis, the phase diagram comprises the cycloidal and conical superstructures only. Highlighting the power of polarized REXS, our results reveal a combination of magnetic phases that suggest a highly unusual competition between antiferromagnetic exchange interactions with Dzyaloshinsky--Moriya spin--orbit coupling of similar strength.

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Wolfgang Simeth, Andreas Bauer, Christian Franz, Aisha Aqeel, Pablo J. Bereciartua Perez, Jennifer A. Sears, Sonia Francoual, Christian H. Back, Christian Pfleiderer. 2023-05-12. Resonant elastic X-ray scattering of antiferromagnetic superstructures in EuPtSi$_{3}$. https://doi.org/10.1103/physrevlett.130.266701

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