Sheet Resistance and Magnetoresistance in Polycrystalline CVD Graphenes

Temperature and magnetic field dependencies of sheet resistance R (T,B) in polycrystalline CVD graphene, investigated in the range of 2≤ T≤ 300 K and magnetic fields 0≤ B≤ 8 T, allowed to determine carrier transport mechanisms in single-layered and twisted CVD graphene. It is shown that for R (T,B) curves for such samples are described by the interference quantum corrections to the Drude conductivity independently on type of precursor and peculiarities of graphene transfer from Cu foil onto the various substrates (glass or SiO2). The twisted CVD graphene samples have demonstrated additional contribution of 2D hopping conductivity into the R (T,B) dependencies. Keywords: graphene, single layer, twisted layers, CVD, carrier transport, magnetoresistance