English

Effective enhancement of the electron-phonon coupling driven by nonperturbative electronic density fluctuations

Strongly Correlated Electrons 2026-03-31 v2

Abstract

We present a dynamical mean-field study of the nonperturbative electronic mechanisms, which may lead to significant enhancements of the electron-phonon coupling in correlated electron systems. Analyzing the effects of electronic correlations on the lowest-order electron-phonon processes, we show that in the proximity of the Mott metal-to-insulator transition of the doped square lattice Hubbard model, where the isothermal charge response becomes particularly large at small momenta, the coupling of electrons to the lattice is strongly increased. This, in turn, induces significant corrections to both the electronic self-energy and phonon-mediated pairing interaction, indicating the possible onset of a strong interplay between lattice and electronic degrees of freedom even for small values of the bare electron-phonon coupling.

Keywords

Cite

@article{arxiv.2503.12113,
  title  = {Effective enhancement of the electron-phonon coupling driven by nonperturbative electronic density fluctuations},
  author = {Emin Moghadas and Matthias Reitner and Tim Wehling and Giorgio Sangiovanni and Sergio Ciuchi and Alessandro Toschi},
  journal= {arXiv preprint arXiv:2503.12113},
  year   = {2026}
}