Electronic and transport properties of zigzag-edge monolayer/bilayer phosphorene nanoribbon junctions under a perpendicular electric field

We study the electronic and transport properties of monolayer/bilayer/bilayer (ML/BL/BL) and monolayer/bilayer/monolayer (ML/BL/ML) zigzag-edge phosphorene nanoribbon (ZPNR) junctions modulated by a perpendicular electric field (PEF). Within the tight-binding model Hamiltonian and by adopting the nonequilibrium Green's function, it is demonstrated that some oscillating conductance plateaus appear for the junctions, and the conductances are suppressed by the applied PEF. Interestingly, the direction of the PEF has different influence on the conductance of both junctions. We further present separately the band structures of the left lead, the central region and right lead, to reveal the reason for different conductance behavior in detail. Our results show that the ML/BL/BL ZPNR junction may be more suitable for the usage of field effect transistor than the ML/BL/ML ZPNR one under a PEF. Moreover, a PEF can be applied to distinguish the bottom?bottom and bottom?up configurations for the ML/BL/ML ZPNR junction.