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arXiv · 0807.2274

LiFeAs: An Intrinsic FeAs-based Superconductor with Tc = 18K

Joshua H. Tapp·Zhongjia Tang·Bing Lv·Kalyan Sasmal·Bernd Lorenz·Paul C. W. Chu·Arnold M. Guloy
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Abstract

The synthesis and properties of LiFeAs, a high-Tc Fe-based superconducting stoichiometric compound, are reported. Single crystal x-ray studies reveal that it crystallizes in the tetragonal PbFCl type (P4/nmm) with a=3.7914(7) A and c=6.364(2) A. Unlike the known isoelectronic undoped intrinsic FeAs compounds, LiFeAs does not show any spin-density wave behavior but exhibits superconductivity at ambient pressures without chemical doping. It exhibits a respectable transition temperature of Tc=18 K with electronlike carriers and a very high critical field, Hc2(0)>80 T. LiFeAs appears to be the chemical equivalent of the infinite layered compound of the high-Tc cuprates.

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Joshua H. Tapp, Zhongjia Tang, Bing Lv, Kalyan Sasmal, Bernd Lorenz, Paul C. W. Chu, Arnold M. Guloy. 2008-08-25. LiFeAs: An Intrinsic FeAs-based Superconductor with Tc = 18K. https://doi.org/10.1103/physrevb.78.060505

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