Band tunneling through double barrier in biased graphene bilayer

We calculate the transport properties of charge carriers in graphene bilayers across symmetric and asymmetric double potential barrier considering energies exceeding the inter-layer coupling where two transport modes exist. Evaluating the transmission and reflection probabilities and corresponding conductances, we show that the transport is sensitive to the distance between the two barriers. Moreover, we explain the characteristic features observed in the numerical calculations, such as resonance tunneling at normal incidence, based on the Febry–Pèrot oscillations and ballistic transmission carried out by the evanescent waves. Finally, we compute the conductance of each mode separately and investigate contributions from inter-mode scattering and show that some geometric potential parameters can be used to control the total conductance of the system. (paper)