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arXiv · 1008.2050

Single crystal growth and superconducting properties of LiFeAs

Bumsung Lee·Seunghyun Khim·Jung Soo Kim·G. R. Stewart·Kee Hoon Kim
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Abstract

We report the successful growth of high quality single crystals of LiFeAs with lateral sizes up to 5 x 5 mm2 by the Sn-flux method. Electrical resistivity studies reveal that the superconducting onset temperature is 18.2 K with a transition width less than 1.1 K and the ratio of room temperature to residual resistivity is about 24. Bulk superconductivity is supported by perfect shielding in the magnetic susceptibility and a clear jump in the specific heat Cp, resulting in deltaCp/T ~ 20.0 mJ/mol*K2. Upper critical field slopes of dHc2c/dT ~ -1.39 and dHc2ab/dT ~ -2.99 T/K near Tc predict zero temperature upper critical fields of Hc2c(0) ~ 17.2 and Hc2ab(0) ~ 36.9 T and coherence lengths of Xi_ab = 4.4 and Xi_c = 2.0 nm in a single band model. This result points to a modest superconducting anisotropy about 2.3 in LiFeAs.

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Bumsung Lee, Seunghyun Khim, Jung Soo Kim, G. R. Stewart, Kee Hoon Kim. 2010-08-12. Single crystal growth and superconducting properties of LiFeAs. https://doi.org/10.1209/0295-5075%2F91%2F67002

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