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arXiv · 1104.0453

Direct observation of local K variation and its correlation to electronic inhomogeneity in (Ba1-xKx)Fe2As2 Pnictide

W. K. Yeoh·B. Gault·X. Y. Cui·C. Zhu·M. P. Moody·L. Li·R. K. Zheng·W. X Li·X. L. Wang·S. X. Dou·C. T. Lin·S. P. Ringer
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Abstract

Local fluctuations in the distribution of dopant atoms are a suspected cause of nanoscale electronic disorder or phase separation observed within the pnictide superconductors. Atom probe tomography results present the first direct observations of dopant nano-clustering in a K-doped 122-phase pnictides. First-principles calculations suggest the coexistence of static magnetism and superconductivity on a lattice parameter length scale over a large range of doping concentrations. Collectively, our results provide evidence for a mixed scenario of phase coexistence and phase separation originating from variation of dopant atom experiments distroibutions.

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W. K. Yeoh, B. Gault, X. Y. Cui, C. Zhu, M. P. Moody, L. Li, R. K. Zheng, W. X Li, X. L. Wang, S. X. Dou, C. T. Lin, S. P. Ringer. 2011-05-18. Direct observation of local K variation and its correlation to electronic inhomogeneity in (Ba1-xKx)Fe2As2 Pnictide. https://doi.org/10.1103/physrevlett.106.247002

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