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Path Integral Computation of Phonon Anharmonicity

Marco Zoli
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Abstract

The partition function of an oscillator disturbed by a set of electron particle paths has been computed by a path integral method which permits to evaluate at any temperature the relevant cumulant terms in the series expansion. The time dependent source current peculiar of the semiclassical Su-Schrieffer-Heeger model induces large electron-phonon anharmonicities on the phonon subsystem. As a main signature of anharmonicity the phonon heat capacity shows a peak whose temperature location strongly varies with the strength of the {\it e-ph} coupling. High energy oscillators are less sensitive to anharmonic perturbations.

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Marco Zoli. 2003-09-26. Path Integral Computation of Phonon Anharmonicity. https://doi.org/10.1140/epjb%2Fe2004-00241-7

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