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arXiv · 2208.07071

The superconducting energy gap in the hole-doped graphene beyond the Migdal's theory

Adam Z. Kaczmarek·Ewa A. Drzazga-Szczęśniak
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Abstract

In this work we analyze impact of non-adiabatic effects on the superconducting energy gap in the hole-doped graphene. By using the Eliashberg formalism beyond the Migdal's theorem, we present that the non-adiabatic effects strongly influence the superconducting energy gap in the exemplary boron-doped graphene. In particular, the non-adiabatic effects, as represented by the first order vertex corrections to the electron-phonon interaction, supplement Coulomb depairing correlations and suppress the superconducting state. In summary, the obtained results confirm previous studies on superconductivity in two-dimensional materials and show that the corresponding superconducting phase may be notably affected by the non-adiabatic effects.

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Adam Z. Kaczmarek, Ewa A. Drzazga-Szczęśniak. 2022-08-15. The superconducting energy gap in the hole-doped graphene beyond the Migdal's theory. https://doi.org/10.12693/aphyspola.143.153

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