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Dominant particle-hole contributions to the phonon dynamics in the spinless one-dimensional Holstein model

S. Sykora·A. Huebsch·K. W. Becker
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Abstract

In the spinless Holstein model at half-filling the coupling of electrons to phonons is responsible for a phase transition from a metallic state at small coupling to a Peierls distorted insulated state when the electron-phonon coupling exceeds a critical value. For the adiabatic case of small phonon frequencies, the transition is accompanied by a phonon softening at the Brillouin zone boundary whereas a hardening of the phonon mode occurs in the anti-adiabatic case. The phonon dynamics studied in this letter do not only reveal the expected renormalization of the phonon modes but also show remarkable additional contributions due to electronic particle-hole excitations.

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S. Sykora, A. Huebsch, K. W. Becker. 2006-09-28. Dominant particle-hole contributions to the phonon dynamics in the spinless one-dimensional Holstein model. https://doi.org/10.1209/epl%2Fi2006-10327-x

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