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arXiv · 0907.2598

Transport properties and the anisotropy of Ba_{1-x}K_xFe_2As_2 single crystals in normal and superconducting states

V. N. Zverev·A. V. Korobenko·G. L. Sun·D. L. Sun·C. T. Lin·A. V. Boris
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Abstract

The transport and superconducting properties of Ba_{1-x}K_xFe_2As_2 single crystals with T_c = 31 K were studied. Both in-plane and out-of plane resistivity was measured by modified Montgomery method. The in-plane resistivity for all studied samples, obtained in the course of the same synthesis, is almost the same, unlike to the out-of plane resistivity, which differ considerably. We have found that the resistivity anisotropy \gamma=\rho_c /\rho_{ab} is almost temperature independent and lies in the range 10-30 for different samples. This, probably, indicates on the extrinsic nature of high out-of-plane resistivity, which may appear due to the presence of the flat defects along Fe-As layers in the samples. This statement is supported by comparatively small effective mass anisotropy, obtained from the upper critical field measurements, and from the observation of the so-called "Friedel transition", which indicates on the existence of some disorder in the samples in c-direction.

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V. N. Zverev, A. V. Korobenko, G. L. Sun, D. L. Sun, C. T. Lin, A. V. Boris. 2009-07-15. Transport properties and the anisotropy of Ba_{1-x}K_xFe_2As_2 single crystals in normal and superconducting states. https://doi.org/10.1134/s0021364009140100

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