Thermodynamics of a continuum Su–Schrieffer–Heeger model

Abstract

The full partition function for an electron–phonon system described by the one dimensional Su–Schrieffer–Heeger model is exactly computed by a path integral method. Mapping the real space Hamiltonian onto the time scale we introduce a temperature dependent range hopping for the electrons. The heat capacity over temperature ratio shows an upturn at low temperatures which is a peculiar feature of the glassy state. The perturbation on the phonon subsystem due to the electron path motion are evaluated by a cumulant expansion of the phonon free energy.