Generalized thermal rectifier model with optimal thermal rectification ratio and its application to Ga₂O₃-based...

Area of Science:

• Condensed Matter Physics
• Materials Science
• Thermal Engineering

Background:

• Thermal rectification is crucial for managing heat in electronic devices.
• Asymmetric heat transport is key to rectifier functionality.

Purpose of the Study:

• To develop a generalized optimization strategy for two-segment thermal rectifiers.
• To maximize the rectification ratio (R) by analyzing interface temperature effects.
• To create an analytical framework for optimizing rectifiers with temperature-dependent thermal conductivities.

Main Methods:

• Utilized Fourier's law for heat transport analysis.
• Developed an analytical framework based on interface temperature and thermal conductivity (κ(T)).
• Employed device-level simulations using the finite-difference time-domain method (energy2D).

Main Results:

• Identified that maximum rectification ratio (R) occurs when interface temperatures are equal in both forward and reverse directions.
• Demonstrated that higher nonlinearity in thermal conductivity enhances the optimized rectification ratio.
• Applied the framework to gallium oxide heterojunctions, evaluating theoretical and real material performance.

Conclusions:

• The developed analytical framework provides an effective strategy for optimizing thermal rectifiers.
• Nonlinear thermal conductivity significantly impacts rectifier performance.
• The findings are validated by device-level simulations, confirming theoretical predictions for gallium oxide devices.