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Electron-phonon interaction and pairing mechanism in superconducting Ca-intercalated bilayer graphene.

ABSTRACT: Using the ab initio anisotropic Eliashberg theory including Coulomb interactions, we investigate the electron-phonon interaction and the pairing mechanism in the recently-reported superconducting Ca-intercalated bilayer graphene. We find that C6CaC6 can support phonon-mediated superconductivity with a critical temperature Tc?=?6.8-8.1?K, in good agreement with experimental data. Our calculations indicate that the low-energy Caxy vibrations are critical to the pairing, and that it should be possible to resolve two distinct superconducting gaps on the electron and hole Fermi surface pockets.

SUBMITTER: Margine ER

PROVIDER: S-EPMC4759825 | biostudies-other | 2016

REPOSITORIES: biostudies-other

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Electron-phonon interaction and pairing mechanism in superconducting Ca-intercalated bilayer graphene.

Margine E R ER Lambert Henry H Giustino Feliciano F

Scientific reports 20160219

Using the ab initio anisotropic Eliashberg theory including Coulomb interactions, we investigate the electron-phonon interaction and the pairing mechanism in the recently-reported superconducting Ca-intercalated bilayer graphene. We find that C6CaC6 can support phonon-mediated superconductivity with a critical temperature Tc = 6.8-8.1 K, in good agreement with experimental data. Our calculations indicate that the low-energy Caxy vibrations are critical to the pairing, and that it should be possi ...[more]

PMID: 26892805

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