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arXiv · 1007.2341

Charge-density-wave instability in the Holstein model with quartic anharmonic phonons

Alain Moise Dikande
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Abstract

The molecular-crystal model, that describes a one-dimensional electron gas interacting with quartic anharmonic lattice vibrations, offers great potentials in the mapping of a relatively wide range of low-dimensional fermion systems coupled to optical phonons onto quantum liquids with retarded interactions. Following a non-perturbative approach involving non-Gaussian partial functional integrations of lattice degrees of freedom, the exact expression of the phonon-mediated two-electron action for this model is derived. With the help of Hubbard-Stratonovich transformation the charge-density-wave instability is examined in the sequel, with particular emphasis on the effect of the quartic anharmonic phonons on the charge-density-wave transition temperature.

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Alain Moise Dikande. 2010-07-14. Charge-density-wave instability in the Holstein model with quartic anharmonic phonons. https://doi.org/10.1143/jpsj.78.094007

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