How to make graphene superconducting

TL;DR

This paper investigates how doping graphene with different adatoms can induce superconductivity, revealing that lithium coverage leads to higher superconducting temperatures than calcium, unlike in graphite intercalated compounds.

Contribution

It demonstrates that adatom doping can induce superconductivity in graphene, with lithium providing notably higher transition temperatures than calcium, contrasting previous GIC behaviors.

Findings

Li-covered graphene is superconducting at higher temperatures than Ca-covered graphene.

Superconductivity depends on the type of adatom used for doping.

Doping graphene with adatoms can enable nanoscale superconducting devices.

Abstract

Graphene is the physical realization of many fundamental concepts and phenomena in solid state-physics, but in the long list of graphene remarkable properties, a fundamental block is missing: superconductivity. Making graphene superconducting is relevant as the easy manipulation of this material by nanolytographic techniques paves the way to nanosquids, one-electron superconductor-quantum dot devices, superconducting transistors at the nano-scale and cryogenic solid-state coolers. Here we explore the doping of graphene by adatoms coverage. We show that the occurrence of superconductivity depends on the adatom in analogy with graphite intercalated compounds (GICs). However, most surprisingly, and contrary to the GIC case, Li covered graphene is superconducting at much higher temperature with respect to Ca covered graphene.