Temperature-Dependent Electronic Ground-State Charge Transfer in van der Waals Heterostructures

Area of Science:

• Condensed Matter Physics
• Materials Science
• Physical Chemistry

Background:

• Electronic charge rearrangement is crucial for heterostructure ground states.
• Charge transfer is influenced by density of states, but temperature effects are understudied, especially in weakly interacting systems.

Purpose of the Study:

• To investigate the temperature dependence of ground-state charge transfer in a specific van der Waals heterostructure.
• To elucidate the underlying mechanisms governing temperature-dependent charge transfer.

Main Methods:

• Experimental observation of charge transfer in a MoS2-based van der Waals heterostructure at varying temperatures (7 K to room temperature).
• State-of-the-art electronic structure calculations incorporating nuclear thermal fluctuations.
• Development of a theoretical model for multicomponent van der Waals heterostructures.

Main Results:

• Ground-state charge transfer increased by a factor of 3 when temperature rose from 7 K to room temperature.
• Electronic structure calculations identified intracomponent electron-phonon coupling and intercomponent electronic coupling as key factors.
• A generalized model was developed to explain charge transfer in similar multicomponent systems.

Conclusions:

• Temperature plays a significant role in modulating charge transfer in van der Waals heterostructures.
• Electron-phonon and electronic coupling mechanisms are critical for understanding temperature-dependent charge transfer.
• The findings provide a new perspective on designing and controlling electronic properties of layered materials.