Ab-initio phonon-defect scattering and thermal conductivity of Graphene, Si, Diamond, InN and BAs

We present parameter-free calculations of thermal conductivity using the Peierls-Boltzmann transport equation combined with an ab-initio Green’s function methodology to describe the scattering of phonons with point defects. Specifically, we include phonon-defect scattering by substitutional atoms and vacancies in Graphene, Si and InN as well as anti-site defects in BAs and Nitrogen-Vacancy centers in Diamond. Our calculations demonstrate the importance of including changes of the interatomic force constants (IFCs) locally near the defect, which yields scattering rates that challenge our intuition built from perturbative approaches. For example, substitutional atoms with larger mass perturbation do not necessarily result in larger scattering rates. Neglecting the changes on the IFCs can result in scattering rates well below an order of magnitude of those from the full calculation. Finally, we discuss important simulation details of the Green’s function methodology, including IFC symmetries, convergence with nearest neighbor shells, and the conundrum of enforcing the acoustic sum rule.