Interband Electron Pairing for Superconductivity from the Breakdown of the Born-Oppenheimer Approximation

Myung-Hwan Whangbo; Shuiquan Deng; Jürgen Köhler; Arndt Simon

doi:10.1002/cphc.201800738

Interband Electron Pairing for Superconductivity from the Breakdown of the Born-Oppenheimer Approximation

Chemphyschem. 2018 Oct 8. doi: 10.1002/cphc.201800738. Online ahead of print.

Authors

Myung-Hwan Whangbo^{1

2

3}, Shuiquan Deng², Jürgen Köhler^{2

4}, Arndt Simon⁴

Affiliations

¹ Department of Chemistry, North Carolina State University, Raleigh, NC 27695-8204, USA.
² State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter (FJIRSM), Chinese Academy of Sciences (CAS), Fuzhou, 350002, China.
³ State key Laboratory of Crystal Materials, Shandong University, Jinan, 250100, China.
⁴ Max-Planck-Institute for Solid State Research, Heisenbergstr. 1, D-70569, Stuttgart, Germany.

PMID: 30296352
DOI: 10.1002/cphc.201800738

Abstract

The origin of interband electron pairing, responsible for enhancing superconductivity, and the factors controlling its strength were examined. We show that interband electron pairing is a natural consequence of breaking down the Born-Oppenheimer approximation during 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 the implications of this observation are discussed.

Keywords: Born-Oppenheimer approximation; Fermi surfaces; interband electron pairing; metals; multiband superconductivity.

Abstract

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