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On the Ginzburg-Landau Analysis of the Upper Critical Field Hc2 in MgB2

I. N. Askerzade·A. Gencer·N. Guclu
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Abstract

Temperature dependence of the upper critical field Hc2 (T) for the superconducting magnesium diboride, MgB2, is studied in the vicinity of Tc by using a two-band Ginzburg-Landau (G-L) theory. The temperature dependence of Hc2 (T) near Tc exhibits a positive curvature. In addition, the calculated temperature dependence and its higher order derivatives are also shown to be in a good agreement with the experimental data. In analogy with the multi-band character of Eliashberg microscopic theory, the positive curvature of Hc2 (T) is described reasonably by solving the two-band of G-L theory.

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I. N. Askerzade, A. Gencer, N. Guclu. 2001-12-12. On the Ginzburg-Landau Analysis of the Upper Critical Field Hc2 in MgB2. https://doi.org/10.1088/0953-2048%2F15%2F2%2F102

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