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arXiv · 2410.03332

Site-projected Thermal Conductivity: Application to defects, interfaces, and homogeneously disordered materials

A. Gautam·Y. G. Lee·C. Ugwumadu·K. Nepal·S. Nakhmanson·D. A. Drabold
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Abstract

With the rapid advance of high-performance computing and electronic technologies, understanding thermal conductivity in materials has become increasingly important. This study presents a novel method: the Site-projected Thermal Conductivity (SPTC) that quantitatively estimates the local (atomic) contribution to heat transport, leveraging the Green-Kubo thermal transport equations. We demonstrate the effectiveness of this approach on disordered and amorphous graphene, amorphous silicon, and grain boundaries in silicon-germanium alloys. Amorphous graphene reveals a percolation behavior for thermal transport. The results highlight the potential of our method to provide new insights into the thermal behavior of materials, offering a promising avenue for materials design and performance optimization.

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A. Gautam, Y. G. Lee, C. Ugwumadu, K. Nepal, S. Nakhmanson, D. A. Drabold. 2024-10-04. Site-projected Thermal Conductivity: Application to defects, interfaces, and homogeneously disordered materials. https://doi.org/10.1002/pssr.202400306

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