Moiré-Engineering-Induced Counteractive Control of Thermal and Electrical Transport in MoSe2/WSe2 Heterostructure.

Moiré engineering provides a powerful method for controlling electrical transport in two-dimensional semiconductors. Meanwhile, moiré engineering also enables the tuning of the interfacial thermal conductance of bilayer materials by means of changing the distance between layers. However, the simultaneous control of electrical and thermal transport in the same moiré-engineered bilayer sample can be challenging. The mechanism underlying the differentiated regulation effect remains elusive. In this work, the electrical and thermal conductivities of the same MoSe2/WSe2 heterostructure were measured simultaneously with a series of precisely controlled twist angles. It is found that as the moiré superlattice period declines with the twist angle increasing from 0° to 30°, the thermal rectification ratio of the heterostructure decreases from 65 to 30%, meanwhile the electrical rectification ratio increases from 100 to 200%. At a critical twist angle of 30° corresponding to the minimum moiré superlattice period, the thermal rectification ratio is minimized, while the electrical rectification undergoes a reversal from a positive to a negative state. This demonstrates that the moiré superlattice provokes different rectifying responses for phonons and electrons. Decreasing the period of the moiré superlattice induces a pronounced enhancement of the asymmetry in the electronic density of states, while the thermal asymmetry is suppressed due to stronger interlayer coupling. These findings furnish fresh perspectives on the moiré-controlled effect and establish a basis for the development of advanced atomic-scale rectifying devices.