Multi-Band Superconductivity and the Steep Band/Flat Band Scenario

@article{BussmannHolder2019MultiBandSA,
  title={Multi-Band Superconductivity and the Steep Band/Flat Band Scenario},
  author={A Bussmann-Holder and Hugo Keller and Arndt Simon and Antonio Bianconi},
  journal={Condensed Matter},
  year={2019}
}
The basic features of multi-band superconductivity and its implications are derived. In particular, it is shown that enhancements of the superconducting transition temperature take place due to interband interactions. In addition, isotope effects differ substantially from the typical BCS scheme as soon as polaronic coupling effects are present. Special cases of the model are polaronic coupling in one band as realized e.g., in cuprates, coexistence of a flat band and a steep band like in MgB2… 

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