  Superconductor-graphene-superconductor (SGS) junction provides a unique
platform to study relativistic electrodynamics of Dirac fermions combined with
proximity-induced superconductivity. We report observation of the Josephson
effect in proximity-coupled superconducting junctions of graphene in contact
with Pb1-xInx (x=0.07) electrodes for temperatures as high as T = 4.8K, with a
large IcRn (~ 255 microV). This demonstrates that Pb1-xInx SGS junction would
facilitate the development of the superconducting quantum information devices
and superconductor-enhanced phase-coherent transport of graphene.
