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

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Moiré engineering offers control over electronic transport in 2D semiconductors.
• Tuning interfacial thermal conductance in bilayers is possible via interlayer distance.
• Simultaneously controlling electrical and thermal transport in moiré heterostructures is challenging.

Purpose of the Study:

• Investigate the differentiated regulation of electrical and thermal transport in moiré-engineered heterostructures.
• Elucidate the underlying mechanisms of distinct electrical and thermal rectification responses.

Main Methods:

• Simultaneous measurement of electrical and thermal conductivities in MoSe2/WSe2 heterostructures.
• Systematic variation of twist angles to control moiré superlattice period.
• Analysis of rectification ratios as a function of twist angle.

Main Results:

• Thermal rectification ratio decreased from 65% to 30% as twist angle increased from 0° to 30°.
• Electrical rectification ratio increased from 100% to 200% with increasing twist angle.
• At 30° twist angle, thermal rectification minimized while electrical rectification reversed from positive to negative.

Conclusions:

• Moiré superlattices induce distinct rectifying responses for phonons and electrons.
• Decreasing moiré period enhances electronic density of states asymmetry but suppresses thermal asymmetry due to interlayer coupling.
• Findings provide insights into moiré-controlled effects and basis for atomic-scale rectifying devices.