Theoretical study on negative differential resistance in transition metal dichalcogenide planar heterostructures

Two types of WS2/MoX2/WS2 (X = S, Se) planar heterostructures driven by bias are theoretically proposed and studied, showing the pronounced negative differential resistance (NDR) effect. It is demonstrated that the maximum peak-to-valley ratio (mPVR) and current peak strongly depend on the temperature, and the enhanced mPVR can be realized by tuning the device length. In particular, type B (X = Se) has a more remarkable NDR effect than type A (X = S). Our work provides promising possibilities for designing and manufacturing future low-power electronic devices based on monolayer transition metal dichalcogenide planar heterostructures under low bias regime.