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arXiv · 1609.00825

Phonon anharmonicity, lifetimes and thermal transport in CH$_3$NH$_3$PbI$_3$ from many-body perturbation theory

Lucy D. Whalley·Jonathan M. Skelton·Jarvist M. Frost·Aron Walsh
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Abstract

Lattice vibrations in CH$_3$NH$_3$PbI$_3$ are strongly interacting, with double well instabilities present at the Brillouin zone boundary. Analysis within a first-principles lattice dynamics framework reveals anharmonic potentials with short phonon quasi-particle lifetimes and mean-free paths. The phonon behaviour is distinct from the inorganic semiconductors GaAs and CdTe where three-phonon interaction strengths are three orders of magnitude smaller. The implications for the applications of hybrid halide perovskites arising from thermal conductivity, band-gap deformation, and charge-carrier scattering through electron-phonon coupling, are presented.

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Lucy D. Whalley, Jonathan M. Skelton, Jarvist M. Frost, Aron Walsh. 2016-09-03. Phonon anharmonicity, lifetimes and thermal transport in CH$_3$NH$_3$PbI$_3$ from many-body perturbation theory. https://doi.org/10.1103/physrevb.94.220301

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