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arXiv · 1411.5841

Effect of long-range interactions on the Kohn-Luttinger mechanism of the Cooper instability in the Shubin-Vonsowsky model

M. Yu. Kagan·V. V. Val'kov·V. A. Mitskan·M. M. Korovushkin
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Abstract

The problem of Cooper instability is studied by implementing the Kohn-Luttinger mechanism in the framework of the Shubin-Vonsowsky model taking into account the intersite Coulomb interactions within the first and second coordination spheres. It is shown that the Kohn-Luttinger renormalization for the effective interaction in the second-order terms of perturbation theory, as well as the inclusion of intersite hoppings in the second and third coordination spheres, significantly affects the interplay between the superconducting phases with $d_{xy}$-, $p$-, $s$-, and $d_{x^2-y^2}$-wave symmetries of the order parameter.

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M. Yu. Kagan, V. V. Val'kov, V. A. Mitskan, M. M. Korovushkin. 2014-11-21. Effect of long-range interactions on the Kohn-Luttinger mechanism of the Cooper instability in the Shubin-Vonsowsky model. https://doi.org/10.1134/s0021364013040085

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