Probing Electronic Band Structure of Monolayer MoS in Gate-Controlled Resonant Tunneling Diodes.

Experimental determination of band structures of monolayer transition metal dichalcogenides (TMDCs) is crucially important in the design and tailoring of the properties of TMDCs. Resonant tunneling spectroscopy (RTS) is an effective technique to probe the band structures of low-dimensional systems by measuring the density of states (DOS) and energy dispersions. Here, we report the investigation of the band structure of monolayer MoS (ML-MoS) in a gate-controlled resonant tunneling diode. Three distinct resonant tunneling kinks are observed in the characteristic current-voltage curves at 0.47, 0.70, and 0.81 V, respectively, which correspond to the conduction band local minimum of ML-MoS at K, Q, and Q points. When applying a large positive gate voltage to enhance ML-MoS conductivity, the three resonant kinks shift to lower bias at 0.10, 0.32, and 0.39 V, respectively, which is in excellent agreement with the theoretical calculations. Our work offers an effective and more precise way to explore the electronic band structures of TMDCs using RTS.