Mean field superconductivity approach in two dimensions: Hydrogen in Graphite

TL;DR

This paper uses BCS theory to estimate the superconducting gap and critical temperature in hydrogen-doped graphite, suggesting potential high-temperature superconductivity in this two-dimensional system.

Contribution

It provides a theoretical calculation of the superconducting gap and critical temperature in hydrogenated graphite using a mean field approach within BCS theory.

Findings

Superconducting gap peaks at ~60 K at specific carrier density

Critical temperature estimates depend on carrier density and effective mass

Results align with experimental hints of granular superconductivity in graphite

Abstract

Within the BCS theory of superconductivity we calculate the superconducting gap at zero temperature for metallic hydrogen-graphene system in order to estimate the superconducting critical temperature of quasi two dimensional highly oriented pyrolytic graphite. The obtained results are given as a function of the hydrogen-induced density of carriers $n$ and their effective mass $m^\star$. The obtained gap shows a Maxwell-like distribution with a maximum of $\sim 60 $K at $n \sim 3 \times 10^{14} $cm$^{-2}$ and $m^\star/m = 1$. The theoretical results are discussed taking into account recent experimental evidence for granular superconductivity in graphite.