English

Beyond the Tamura model of phonon-isotope scattering

Materials Science 2024-04-18 v2

Abstract

The Tamura model is a particular type of 1st^{\text{st}} Born approximation of the phonon-isotope scattering problem. The expression for the mode-resolved phonon-isotope scattering rates in this model, derived in 1983, is still widely used in ab initio transport calculations. While the original work emphasized its applicability to low-energy acoustic phonons only, it has, nevertheless, been also applied to optical phonons in the field of phonon transport. The model has the salient feature of being a perturbation theory on top of a virtual crystal background. As such, this approach does not correspond to the proper methodology for solving the phonon-substitution defect problem in the respective limit. Here, we explore three avenues to go beyond the Tamura model and carry out calculations on a set of common materials to compare the different approaches. This work allows a systematic improvement of the treatment of phonon-isotope scattering in ab initio phonon transport, while unifying it with the general phonon-substitution scattering problem.

Keywords

Cite

@article{arxiv.2401.04473,
  title  = {Beyond the Tamura model of phonon-isotope scattering},
  author = {Nakib H. Protik and Claudia Draxl},
  journal= {arXiv preprint arXiv:2401.04473},
  year   = {2024}
}