Crossover from Efros-Shklovskii to Mott variable range hopping in monolayer epitaxial graphene grown on SiC

We report variable range hopping (VRH) transport in monolayer epitaxial graphene grown on SiC. A crossover from Efros-Shklovskii (E-S) VRH to Mott VRH can be observed by increasing the magnetic field applied perpendicular to the plane of graphene or by a low-temperature vacuum annealing process. Our new experimental results suggest that monolayer graphene on SiC is an interesting platform for probing VRH and crossover between different VRH regimes in a strongly disordered system.