Coulomb drag study in graphene/GaAs bilayer system with the effect of local field correction and dielectric medium

Abstract

The drag resistivity is measured numerically for electron-electron (e-e) and electron-hole (e-h) coupled layer system composed of single layer graphene and two-dimensional (2D) GaAs layer separated by a barrier. The system is studied within the model of random phase approximation (RPA) and taking into account the static local field correction (LFC) and layer thickness effects in the Ballistic/Boltzmann regime. We have shown analytical expressions of non-linear susceptibility function and effective interlayer Coulomb interaction for non homogeneous dielectric environment at low temperature, high density and large interlayer separation limit. Exchange and correlation effects enhanced the drag resistivity by considering the static local field correction. Width of the layer and interlayer distance dependent local form factors (LFF) are obtained from the solution of the Poisson equation for a multi-layer dielectric medium. The effects of LFC and LFF are the function of bare inter- and intra-layer potential, which enhances the drag resistivity compare to simply measured RPA results. Enhanced drag resistivity also measured for e-h bilayer system where the hole layer is considered for 2D GaAs (drag layer), cause of larger effective mass of hole compare to the electron. Similarly, e-e and e-h bilayer system measured the enhanced drag resistivity due to LFC effects.