2008/03/26 by Mazin, I. I., Balatsky, A. V.
#FOS: Physical sciences #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Superconductivity (cond-mat.supr-con)
paper · doi:10.48550/arxiv.0803.3765
Recent observation of proximity effect \citeMorpurgo:2007 has ignited interest in superconductivity in graphene and its derivatives. We consider Ca-intercalated graphene bilayer and argue that it is a superconductor, and likely with a sizeable Tc. We find substantial and suggestive similarities between Ca-intercalated bilayer (C6CaC6), and CaC6 , an established superconductor with Tc = 11.5 K. In particular, the nearly free electron band, proven to be instrumental for superconductivity in intercalated graphites, does cross the chemical potential in (C6CaC% 6), despite the twice smaller doping level, satisfying the so-called \textquotedblleft Cambridge criterion\textquotedblright . Calculated properties of zone-center phonons are very similar to those of CaC%6. This suggests that the critical temperature would probably be on the same scale as in CaC6.