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Superconducting properties of MgB2 from first principles

A. Floris·G. Profeta·N. N. Lathiotakis·M. Lüders·M. A. L. Marques·C. Franchini·E. K. U. Gross·A. Continenza·S. Massidda
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Abstract

Solid MgB$_2$ has rather interesting and technologically important properties, such as a very high superconducting transition temperature. Focusing on this compound, we report the first non-trivial application of a novel density-functional-type theory for superconductors, recently proposed by the authors. Without invoking any adjustable parameters, we obtain the transition temperature, the gaps, and the specific heat of MgB$_2$ in very good agreement with experiment. Moreover, our calculations show how the Coulomb interaction acts differently on s and p states, thereby stabilizing the observed superconducting phase.

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A. Floris, G. Profeta, N. N. Lathiotakis, M. Lüders, M. A. L. Marques, C. Franchini, E. K. U. Gross, A. Continenza, S. Massidda. 2005-08-31. Superconducting properties of MgB2 from first principles. https://doi.org/10.1103/physrevlett.94.037004

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