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arXiv · 0708.2117

Pressure-induced Superconductivity in CaLi2

T. Matsuoka·M. Debessai·J. J. Hamlin·A. K. Gangopadhyay·J. S. Schilling
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Abstract

A search for superconductivity has been carried out on the hexagonal polymorph of Laves-phase CaLi2, a compound for which Feng, Ashcroft, and Hoffmann predict highly anomalous behavior under pressure. No superconductivity is observed above 1.10 K at ambient pressure. However, high-pressure ac susceptibility and electrical resistivity studies to 81 GPa reveal bulk superconductivity in CaLi2 at temperatures as high as 13 K. The normal-state resistivity shows a dramatic increase with pressure.

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T. Matsuoka, M. Debessai, J. J. Hamlin, A. K. Gangopadhyay, J. S. Schilling. 2008-02-20. Pressure-induced Superconductivity in CaLi2. https://doi.org/10.1103/physrevlett.100.197003

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