Ab Initio Phonon Dispersions for PbTe

Jiming An; Alaska Subedi; David J. Singh

doi:10.1016/j.ssc.2008.09.027

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arXiv · 0806.2727

Ab Initio Phonon Dispersions for PbTe

Jiming An·Alaska Subedi·David J. Singh

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Abstract

We report first principles calculations of the phonon dispersions of PbTe both for its observed structure and under compression. At the experimental lattice parameter we find a near instability of the optic branch at the zone center, in accord with experimental observations.This hardens quickly towards the zone boundary. There is also a very strong volume dependence of this mode, which is rapidly driven away from an instability by compression. These results are discussed inrelation to the thermal conductivity of the material.

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Jiming An, Alaska Subedi, David J. Singh. 2008-07-08. Ab Initio Phonon Dispersions for PbTe. https://doi.org/10.1016/j.ssc.2008.09.027

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