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arXiv · 0902.0806

The Synthesis and Characterization of LiFeAs and NaFeAs

C. W. Chu·F. Chen·M. Gooch·A. M. Guloy·B. Lorenz·B. Lv·K. Sasmal·Z. J. Tang·J. H. Tapp·Y. Y. Xue
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Abstract

The newest homologous series of superconducting As-pnictides, LiFeAs (Li111) and NaFeAs (Na111) have been synthesized and investigated. Both crystallize with the layered tetragonal anti-PbFCl-type structure in P4/nmm space group. Polycrystalline samples and single-crystals of Li111 and Na111 display superconducting transitions at ~ 18 K and 12-25 K, respectively. No magnetic order has been found in either compound, although a weak magnetic background is clearly in evidence. The origin of the carriers and the stoichiometric compositions of Li111 and Na111 were explored.

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C. W. Chu, F. Chen, M. Gooch, A. M. Guloy, B. Lorenz, B. Lv, K. Sasmal, Z. J. Tang, J. H. Tapp, Y. Y. Xue. 2009-02-04. The Synthesis and Characterization of LiFeAs and NaFeAs. https://doi.org/10.1016/j.physc.2009.03.016

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