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arXiv · 1107.2211

Revealing the dual nature of magnetism in iron pnictides and iron chalcogenides using x-ray emission spectroscopy

H. Gretarsson·A. Lupascu·Jungho Kim·D. Casa·T. Gog·W. Wu·S. R. Julian·Z. J. Xu·J. S. Wen·G. D. Gu·R. H. Yuan·Z. G. Chen·N. -L. Wang·S. Khim·K. H. Kim·M. Ishikado·I. Jarrige·S. Shamoto·J. -H. Chu·I. R. Fisher·Young-June Kim
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Abstract

We report Fe K beta x-ray emission spectroscopy study of local magnetic moments in various iron based superconductors in their paramagnetic phases. Local magnetic moments are found in all samples studied: PrFeAsO, Ba(Fe,Co)2As2, LiFeAs, Fe1+x(Te,Se), and A2Fe4Se5 (A=K, Rb, and Cs). The moment size varies significantly across different families. Specifically, all iron pnictides samples have local moments of about 1 $\mu_B$/Fe, while FeTe and K2Fe4Se5 families have much larger local moments of ~2$\mu_B$/Fe, ~3.3$\mu_B$/Fe, respectively. In addition, we find that neither carrier doping nor temperature change affects the local moment size.

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H. Gretarsson, A. Lupascu, Jungho Kim, D. Casa, T. Gog, W. Wu, S. R. Julian, Z. J. Xu, J. S. Wen, G. D. Gu, R. H. Yuan, Z. G. Chen, N. -L. Wang, S. Khim, K. H. Kim, M. Ishikado, I. Jarrige, S. Shamoto, J. -H. Chu, I. R. Fisher, Young-June Kim. 2011-07-12. Revealing the dual nature of magnetism in iron pnictides and iron chalcogenides using x-ray emission spectroscopy. https://doi.org/10.1103/physrevb.84.100509

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