Influence of correlated impurities on electrical conductivity in bilayer graphene double layer systems

摘要

We study the electrical conductivity σ of three bilayer graphene (BLG) double layer systems, taking into account the presence of correlations of charged impurities. Using the Boltzmann transport equation with relaxation time approximation and the continuum model for structure factor S(q), we calculate the conductivity of the first BLG layer in presence of the second layer (BLG, monolayer graphene (MLG), two dimensional electric gas (2DEG)) due to screened Coulomb scattering at T =0K for different values of correlation length r_0, interlayer distance d, dielectric constant ε_2, ε_3 and 2DEG material parameters. We show that σ increases with decreasing d for all values of r_0 and increases strongly (remains almost unchanged) with increasing ε_2(ε_3). It is found that σ is almost independent of ε_3 for BLG-2DEG system and the influence of correlation on σ is negligible for low impurity concentration in layer I (n_(i1)≤10~(12)cm~(-2)).