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arXiv · 1810.04305

Interband electron pairing for superconductivity from the breakdown of the Born-Oppenheimer approximation

Myung-Hwan Whangbo·Shuiquan Deng·Jürgen Köhler·Arndt Simon
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Abstract

The origin of interband electron pairing responsible for enhancing superconductivity and the factors controlling its strength were examined. We show that the interband electron pairing is a natural consequence of breaking down the Born-Oppenheimer approximation during the electron-phonon interactions. Its strength is determined by the pair-state excitations around the Fermi surfaces that take place to form a superconducting state. Fermi surfaces favorable for the pairing were found and its implications were discussed.

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Myung-Hwan Whangbo, Shuiquan Deng, Jürgen Köhler, Arndt Simon. 2018-10-10. Interband electron pairing for superconductivity from the breakdown of the Born-Oppenheimer approximation. https://doi.org/10.1002/cphc.201800738

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