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Anisotropy of the upper critical field in superconductors with anisotropic gaps. Anisotropy parameters of MgB2

P. Miranovic·K. Machida·V. G. Kogan
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Abstract

The upper critical field Hc2 is evaluated for weakly-coupled two-band superconductors. By modeling the actual bands and the gap distribution of MgB2 by two Fermi surface spheroids with average parameters of the real material, we show that H_{c2,ab}/H_{c2,c} increases with decreasing temperature in agreement with available data.

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P. Miranovic, K. Machida, V. G. Kogan. 2002-07-05. Anisotropy of the upper critical field in superconductors with anisotropic gaps. Anisotropy parameters of MgB2. https://doi.org/10.1143/jpsj.72.221

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