Tunneling conductance of hybrid bilayer-single graphene junctions

Abstract

Abstract We study the tunneling effect of two different junctions based on graphene. Firstly, we consider gapped monolayer graphene (MLG) bridging AA-bilayer graphene (BLG), and secondly, AB stacking. These two systems display a significant decrease in transmission in both setups, showing the adjustability of conductance through gap size manipulation. Furthermore, we identify distinct characteristics in both stackings, including Fano resonances and Fabry-Pérot-like oscillations. Examining conductance as a function of BLG region width gives away varying peaks in the conductance profile for both stackings, exhibiting diverse periods and shapes. We demonstrate that under specific parameter conditions, tunneling leads to zero conductance, contrasting with the case without bias. The coexistence of gap and bias introduces a complex pattern in conductance peaks, reflecting fluctuations in amplitude and frequency. Notably, our findings indicate that the gap induces a noteworthy shift in the conductance profile in AB stacking, suggesting a modification of electronic properties. In AA stacking, minima are particularly evident in the conductance profile, especially for small bias values.