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arXiv · 1308.3483

Theory of temperature dependent phonon-renormalized properties

Bartomeu Monserrat·G. J. Conduit·R. J. Needs
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Abstract

We present a general harmonic theory for the temperature dependence of phonon-renormalized properties of solids. Firstly, we formulate a perturbation theory in phonon-phonon interactions to calculate the phonon renormalization of physical quantities. Secondly, we propose two new schemes for extrapolating phonon zero-point corrections from temperature dependent data that improve the accuracy by an order of magnitude compared to previous approaches. Finally, we consider the low-temperature limit of the class of observables that includes the electronic band gap, obtaining a $T^4$ dependence in three dimensions, $T^2$ in two dimensions, and $T^{3/2}$ in one dimension.

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Bartomeu Monserrat, G. J. Conduit, R. J. Needs. 2013-08-15. Theory of temperature dependent phonon-renormalized properties. https://doi.org/10.1103/physrevb.90.184302

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