Transport properties of MoS2/V7(Bz)8 and graphene/V7(Bz)8 vdW junctions tuned by bias and gate voltages

Abstract

The MoS₂/V₇(Bz)₈ and graphene/V₇(Bz)₈ vdW junctions are designed and the transport properties of their four-terminal devices are comparatively investigated based on density functional theory (DFT) and the nonequilibrium Green's function (NEGF) technique. The MoS₂ and graphene nanoribbons act as the source-to-drain channel and the spin-polarized one-dimensional (1D) benzene-V multidecker complex nanowire (V₇(Bz)₈) serves as the gate channel. Gate voltages applied on V₇(Bz)₈ exert different influences of electron transport on MoS₂/V₇(Bz)₈ and graphene/V₇(Bz)₈. In MoS₂/V₇(Bz)₈, the interplay of source and gate bias potentials could induce promising properties such as negative differential resistance (NDR) behavior, output/input current switching, and spin-polarized currents. In contrast, the gate bias plays an insignificant effect on the transport along graphene in graphene/V₇(Bz)₈. This dissimilarity is attributed to the fact that the conductivity follows the sequence of MoS₂ < V₇(Bz)₈ < graphene. These transport characteristics are examined by analyzing the conductivity, the currents, the local density of states (LDOS), and the transmission spectra. These results are valuable in designing multi-terminal nanoelectronic devices.