Path integral computation of phonon anharmonicity

M. Zoli ()

The European Physical Journal B: Condensed Matter and Complex Systems, 2004, vol. 40, issue 1, 79-86

Abstract: The partition function of an oscillator disturbed by a set of electron particle paths has been computed by a path integral formalism which permits to evaluate at any temperature the relevant cumulant terms in the series expansion. The low temperature cutoffs in the anharmonic cumulant series are determined fulfilling the constraint of the third law of thermodynamics. The general method here proposed has been applied to the semiclassical Su-Schrieffer-Heeger model whose time dependent source current is linear in the oscillator displacement field. We find that this peculiar current induces large electron-phonon anharmonicities on the phonon subsystem. As a signature of anharmonicity the phonon heat capacity shows a peak whose temperature location strongly varies with the strength of the e-ph coupling. Since the electron hopping potential provides a sizeable background in the low and intermediate temperature range, such a peak is partly smeared in the total heat capacity. Low energy oscillators are more sensitive to anharmonic perturbations. Copyright Springer-Verlag Berlin/Heidelberg 2004

Date: 2004
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
http://hdl.handle.net/10.1140/epjb/e2004-00241-7 (text/html)
Access to full text is restricted to subscribers.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:spr:eurphb:v:40:y:2004:i:1:p:79-86

Ordering information: This journal article can be ordered from
http://www.springer.com/economics/journal/10051

DOI: 10.1140/epjb/e2004-00241-7

Access Statistics for this article

The European Physical Journal B: Condensed Matter and Complex Systems is currently edited by P. Hänggi and Angel Rubio

More articles in The European Physical Journal B: Condensed Matter and Complex Systems from Springer, EDP Sciences
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().