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Theory of fluctuations in a two-band superconductor

A. E. Koshelev·A. A. Varlamov·V. M. Vinokur
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Abstract

A theory of fluctuations in two-band superconductor MgB$_{2}$ is developed. Since the standard Ginzburg-Landau (GL) approach fails in description of its properties, we generalize it basing on the microscopic theory of a two-band superconductor. Calculating the microscopic fluctuation propagator, we build up the nonlocal two-band GL functional and the corresponding time-dependent GL equations. This allows us to calculate the main fluctuation observables such as fluctuation specific heat and conductivity.

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A. E. Koshelev, A. A. Varlamov, V. M. Vinokur. 2004-12-30. Theory of fluctuations in a two-band superconductor. https://doi.org/10.1103/physrevb.72.064523

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