Superconductivity from energy fluctuations in dilute quantum critical polar metals

@article{Volkov2022SuperconductivityFE,
  title={Superconductivity from energy fluctuations in dilute quantum critical polar metals},
  author={Pavel A. Volkov and Premala Chandra and Piers Coleman},
  journal={Nature Communications},
  year={2022},
  volume={13}
}
Superconductivity in low carrier density metals challenges the conventional electron-phonon theory due to the absence of retardation required to overcome Coulomb repulsion. Here we demonstrate that pairing mediated by energy fluctuations, ubiquitously present close to continuous phase transitions, occurs in dilute quantum critical polar metals and results in a dome-like dependence of the superconducting Tc on carrier density, characteristic of non-BCS superconductors. In quantum critical polar… 

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