Non-uniform Brillouin zone sampling for thermal transport in layered materials

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Physics

Background:

• Lattice thermal conductivity in layered materials is crucial for thermal management applications.
• Traditional uniform phonon sampling in Brillouin zone calculations is computationally intensive.
• Long-wavelength phonon modes significantly influence thermal conductivity in these materials.

Purpose of the Study:

• To develop an efficient non-uniform Brillouin zone sampling method for predicting lattice thermal conductivity in layered materials.
• To reduce the computational cost of thermal conductivity calculations.
• To maintain accuracy in thermal conductivity predictions.

Main Methods:

• Implemented a non-uniform Brillouin zone sampling approach within the Boltzmann transport equation framework.
• Optimized phonon sampling using grid cutoff distance and grid ratio parameters.
• Applied the method to single-layer graphene and bulk MoS2.

Main Results:

• Achieved a 10-fold reduction in computational cost for phonon scattering calculations.
• Maintained thermal conductivity prediction accuracy within 12% compared to uniform grid methods.
• Demonstrated the effectiveness of selective phonon sampling.

Conclusions:

• The developed non-uniform sampling method offers a computationally efficient alternative for predicting lattice thermal conductivity in layered materials.
• This approach optimizes computational resources without sacrificing significant accuracy.
• The findings have implications for materials design and thermal management strategies.