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arXiv · 1305.0054

Spin polarization of Ru in superconducting Ba(Fe$_{0.795}$Ru$_{0.205}$)$_2$As$_2$ studied by x-ray resonant magnetic scattering

M. G. Kim·J. Soh·J. Lang·M. P. M. Dean·A. Thaler·S. L. Bud'ko·P. C. Canfield·E. Bourret-Courchesne·A. Kreyssig·A. I. Goldman·R. J. Birgeneau
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Abstract

We have employed the x-ray resonant magnetic scattering (XRMS) technique at the Ru $L_2$ edge of the Ba(Fe$_{1-x}$Ru$_x$)$_2$As$_2$ ($x = 0.205$) superconductor. We show that pronounced resonance enhancements at the Ru $L_2$ edge are observed at the wave vector which is consistent with the antiferromagnetic propagation vector of the Fe in the undoped BaFe$_2$As$_2$. We also demonstrate that the XRMS signals at the Ru $L_2$ edge follow the magnetic ordering of the Fe with a long correlation length, $ξ_{ab} > 2850\pm400$ Å. Our experimental observation shows that the Ru is spin-polarized in Ba(Fe$_{1-x}$Ru$_x$)$_2$As$_2$ compounds.

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M. G. Kim, J. Soh, J. Lang, M. P. M. Dean, A. Thaler, S. L. Bud'ko, P. C. Canfield, E. Bourret-Courchesne, A. Kreyssig, A. I. Goldman, R. J. Birgeneau. 2013-07-23. Spin polarization of Ru in superconducting Ba(Fe$_{0.795}$Ru$_{0.205}$)$_2$As$_2$ studied by x-ray resonant magnetic scattering. https://doi.org/10.1103/physrevb.88.014424

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