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arXiv · 1905.09174

Thermally-Enhanced Fr\"ohlich Coupling in SnSe

Fabio Caruso·Maria Troppenz·Santiago Rigamonti·Claudia Draxl
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Abstract

To gain insight into the peculiar temperature dependence of the thermoelectric material SnSe, we employ many-body perturbation theory and explore the influence of the electron-phonon interaction on its electronic and transport properties. We show that a lattice dynamics characterized by soft highly-polar phonons induces a large thermal enhancement of the Fr\"ohlich interaction. We account for these phenomena in ab-initio calculations of the photoemission spectrum and electrical conductivity at finite temperature, unraveling the mechanisms behind recent experimental data. Our results reveal a complex interplay between lattice thermal expansion and Fr\"ohlich coupling, providing a new rationale for the in-silico prediction of transport coefficients of high-performance thermoelectrics.

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Fabio Caruso, Maria Troppenz, Santiago Rigamonti, Claudia Draxl. 2019-05-22. Thermally-Enhanced Fr\"ohlich Coupling in SnSe. https://doi.org/10.1103/physrevb.99.081104

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