Possible high-temperature superconductivity in multilayer graphane: can the cuprates be beaten?

TL;DR

This paper investigates the potential for high-temperature superconductivity in multilayer graphane, showing that interlayer coupling can significantly raise the critical temperature above that of cuprates, with implications for future materials.

Contribution

It demonstrates that multilayer hydrogenized graphene can achieve superconductivity at temperatures exceeding cuprates due to interlayer stabilization.

Findings

Single-layer system has a mean-field $T_c$ around 80-90K.

Fluctuations do not significantly reduce the critical temperature.

Multilayer system can reach $T_c$ around 150K, surpassing cuprates.

Abstract

We analyze a possible superconductivity in the hole-doped system of layered hydrogenized graphene by taking into account thermal fluctuations of the order parameter. In particular, we demonstrate that in the one-layer case the values of the high mean-field (MF) critical temperature $T_{c}^{MF}\sim 80-90K$, predicted recently by Savini et al \cite{Savini}, do not alter significantly due to the fluctuations, and the Berezinskii-Kosterlitz-Thouless (BKT) critical temperature of the vortex superconductivity is almost the same as the MF temperature at doping 0.01-0.1. We show that in the case of multilayer system, when the coupling between the layers stabilizes the superconducting phase in the form of fluxon superconductivity, the critical temperature $T_{c}$ can increase dramatically to the values $\sim 150K$, higher than the corresponding values in cuprates under ambient pressure.