The critical field and specific heat in the electron- and hole-doped graphene superconductors

TL;DR

This paper investigates how electron- and hole-doping affect superconducting properties of graphene, revealing electron doping's superior enhancement of critical magnetic field and specific heat through Migdal-Eliashberg analysis.

Contribution

It applies the Migdal-Eliashberg formalism to analyze doping effects on graphene's superconducting properties, highlighting the greater effectiveness of electron doping.

Findings

Electron doping enhances critical magnetic field more than hole doping.

Electron doping increases specific heat more significantly.

Thermodynamic ratios align with BCS theory predictions.

Abstract

Doping is one of the most prominent techniques to alter properties of a given material. Herein, the influence of the electron- and hole-doping on the selected superconducting properties of graphene are considered. In details, the Migdal-Eliashberg formalism is employed to analyze the specific heat and the critical magnetic field in the representative case of graphene doped with nitrogen or boron, respectively. It is found that the electron doping is much more favorable in terms of enhancing the aforementioned properties than its hole counterpart. These findings are appropriately summarized by the means of the dimensionless thermodynamic ratios, familiar in the Bardeen-Cooper-Schrieffer theory. To this end, the perspectives for future research on superconductivity in graphene are drawn.