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Anisotropic critical fields of MgB2 single crystals

T. Dahm·A. I. Posazhennikova·K. Maki
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Abstract

The recently discovered superconductivity in MgB2 has created the world sensation. In spite of the relatively high superconducting transition temperature Tc=39K, the superconductivity is understood in terms of rare two gap superconductor with energy gaps attached to the sigma- and pi-band. However, this simple model cannot describe the temperature dependent anisotropy in H_c2 or the temperature dependence of the anisotropic magnetic penetration depth. Here we propose a model with two anisotropic energy gaps with different shapes. Indeed the present model describes a number of pecularities of MgB2 which have been revealed only recently through single crystal MgB2.

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T. Dahm, A. I. Posazhennikova, K. Maki. 2002-07-22. Anisotropic critical fields of MgB2 single crystals. https://arxiv.org/abs/cond-mat/0207521

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