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arXiv · 1106.6311

Superconductivity near Pomeranchuk instabilities in the spin channel

Daniel G. Barci·Paulo S. A. Bonfim
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Abstract

We study the competition between a Pomeranchuk instability in the spin channel with angular momentum $\ell=1$ and an attractive interaction, favoring Cooper-pair formation. We found that the superconducting gap strongly suppresses the phase space for the Pomeranchuk instability. We computed a mean-field phase diagram displaying a first order transition between two superconductor phases with different symmetries: p-wave (with spontaneously generated spin-orbit interaction) and s-wave for greater values of the coupling constant. Moreover, we have looked for a possible modulated superconducting phase. We have found that this phase appears only as a meta-stable state in the strong coupling regime.

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Daniel G. Barci, Paulo S. A. Bonfim. 2013-04-07. Superconductivity near Pomeranchuk instabilities in the spin channel. https://doi.org/10.1142/s0217984913501029

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