Electronic structures and transport properties of a MoS2–NbS2 nanoribbon lateral heterostructure

Abstract

Lateral heterostructures built from an armchair MoS₂ nanoribbon (AMoS₂NR) and an armchair NbS₂ nanoribbon (ANbS₂NR) were studied based on first-principles calculations and a non-equilibrium Green's function method. It is found that the work function of the AMoS₂NR shows substantial oscillation with increasing nanoribbon width, which is different from the work functions of other kinds of nanoribbons. The AMoS₂NR–ANbS₂NR lateral heterostructure exhibits an anomalous transport gap that is much larger than the bandgap of the AMoS₂NR. As a result, a field effect transistor with AMoS₂NR as the channel and ANbS₂NRs as electrodes has high on–off ratios of 10⁶–10⁷ and a tiny leakage current of the order of 10⁻⁸ μA. These results suggest that lateral metal–semiconductor heterostructures of transition metal dichalcogenides may have potential applications in nanodevices with low energy consumption.