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Role of the superconducting gap opening on vertex corrections

E. Cappelluti·C. Grimaldi·L. Pietronero
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Abstract

The nonadiabatic effects due to the breakdown of Migdal's theorem in high-$T_c$ superconductors are strongly affected by the opening of the superconducting gap. Here we report how the momentum-frequency dependence of vertex corrections is modified by the gap. A general effect is that the positive region of the vertex corrections is increased leading to an enhancement of their relevance. This has a number of physical consequences that we discuss in details in relation to specific experiments.

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E. Cappelluti, C. Grimaldi, L. Pietronero. 1998-01-22. Role of the superconducting gap opening on vertex corrections. https://arxiv.org/abs/cond-mat/9801232

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