Phonon-mediated superconductivity in low carrier-density systems

  title={Phonon-mediated superconductivity in low carrier-density systems},
  author={Maria N. Gastiasoro and Andrey V. Chubukov and Rafael M. Fernandes},
  journal={Physical Review B},
Motivated by the observation of superconductivity in SrTiO$_3$ and Bi, we analyze phonon-mediated superconductivity in three-dimensional systems at low carrier density, when the chemical potential $\mu$ (equal to Fermi energy at $T=0$) is comparable to or even smaller than the characteristic phonon frequency $\omega_L$. We consider the attractive part of the Bardeen-Pines pairing interaction, in which the frequency-dependent electron-phonon interaction is dressed by the Coulomb potential. This… 

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