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arXiv · 2608.09039

Anharmonic dephasing in the electron-phonon interaction

Mingran Kong·Bartomeu Monserrat
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Abstract

Electron-phonon coupling has been a central topic in condensed matter physics for decades, and firstprinciples methods have demonstrated remarkable success in quantitatively capturing its role in a wide variety of physical phenomena and materials. Conventional calculations of electron-phonon coupling typically assume that phonons have infinite lifetimes, but phonons can exhibit finite lifetimes due to anharmonic phonon-phonon interactions. In this work, we derive an expression for the electron-phonon coupling scattering rates including the effects of anharmonic three-phonon interactions, which lead to phonon dephasing and finite phonon lifetimes. We also describe a first-principles implementation of this anharmonic electron-phonon coupling which can be seamlessly integrated within existing workflows for the evaluation of electron-phonon and phonon-phonon coupling interactions. Finally, we present calculations of electron-phonon scattering rates including phonon dephasing in a range of materials, and discuss the different microscopic mechanisms by which anharmonic phonons influence electron-phonon coupling. This study establishes the importance of finite phonon lifetimes in the evaluation of electron-phonon coupling, and provides a platform to explore these effects in a wide range of materials and phenomena.

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Mingran Kong, Bartomeu Monserrat. 2026-08-10. Anharmonic dephasing in the electron-phonon interaction. https://doi.org/10.1103/1jf8-sx2w

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