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arXiv · 1708.03301

Superconductivity under pressure: application of the functional derivative

G. I. González-Pedreros·R. Baquero
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Abstract

In this paper, we calculate the superconducting critical temperature as a function of pressure, Tc(P ), using a method based on the functional derivative of the critical temperature with the Eliashberg function, dTc/dA2F. The coulomb electron-electron repulsion parameter, mu*(p) at each pressure is obtained in a consistent way by solving the linearized Migdal-Eliashberg equation. This method requires as the starting input only the knowledge of Tc(P ) at the starting pressure. It applies to superconductors for which the Migdal-Eliashberg equations hold. We study Al, a typical BCS weak coupling superconductor with a low Tc . Our results of Tc(P ) as a function of pressure for Al show an excellent agreement with the calculations of Profeta et al. (Phys. Rev. Lett.96, 047003 (2006)) which agree well with experiment.

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G. I. González-Pedreros, R. Baquero. 2017-08-10. Superconductivity under pressure: application of the functional derivative. https://arxiv.org/abs/1708.03301

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