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arXiv · 0812.3024

Magnetic structure of RuSr$_2$GdCu$_2$O$_8$ determined by resonant x-ray diffraction

B. Bohnenbuck·I. Zegkinoglou·J. Strempfer·C. S. Nelson·H. -H. Wu·C. Schüßler-Langeheine·M. Reehuis·E. Schierle·Ph. Leininger·T. Herrmannsdörfer·J. C. Lang·G. Srajer·C. T. Lin·B. Keimer
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Abstract

X-ray diffraction with photon energies near the Ru L$_2$-absorption edge was used to detect resonant reflections characteristic of a G-type superstructure in RuSr$_2$GdCu$_2$O$_8$ single crystals. A polarization analysis confirms that these reflections are due to magnetic order of Ru moments, and the azimuthal-angle dependence of the scattering amplitude reveals that the moments lie along a low-symmetry axis with substantial components parallel and perpendicular to the RuO$_2$ layers. Complemented by susceptibility data and a symmetry analysis of the magnetic structure, these results reconcile many of the apparently contradictory findings reported in the literature.

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B. Bohnenbuck, I. Zegkinoglou, J. Strempfer, C. S. Nelson, H. -H. Wu, C. Schüßler-Langeheine, M. Reehuis, E. Schierle, Ph. Leininger, T. Herrmannsdörfer, J. C. Lang, G. Srajer, C. T. Lin, B. Keimer. 2008-12-16. Magnetic structure of RuSr$_2$GdCu$_2$O$_8$ determined by resonant x-ray diffraction. https://doi.org/10.1103/physrevlett.102.037205

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