Coexistence of superconductivity and charge density wave in a correlated regime

E. J. Calegari; L. C. Prauchner; A. C. Lausmann; S. G. Magalhaes

doi:10.1016/j.physleta.2026.131380

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arXiv · 2601.06326

Coexistence of superconductivity and charge density wave in a correlated regime

E. J. Calegari·L. C. Prauchner·A. C. Lausmann·S. G. Magalhaes

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Abstract

To investigate the coexistence of superconductivity and charge density wave (CDW) in a correlated regime, we employ the Green's functions formalism, as well as the Hubbard-I approximation, as a way to introduce the correlations into the problem, in the form of a repulsive Coulomb interaction $U$. In addition, we investigate the effects of second-nearest neighbor hopping $t_1$ on a pure CDW state. The analysis of the results show that, for small values of $t_1$, both CDW and superconducting gaps compete for the same region on the Fermi surface. The increase of $t_1$ decreases the competition and may lead the system to a coexistence regime. Effects of temperature in the coexistence regime, are also investigated.

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E. J. Calegari, L. C. Prauchner, A. C. Lausmann, S. G. Magalhaes. 2026-01-09. Coexistence of superconductivity and charge density wave in a correlated regime. https://doi.org/10.1016/j.physleta.2026.131380

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