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Analytical approach to the quantum-phase transition in the one-dimensional spinless Holstein model

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

We study the one-dimensional Holstein model of spinless fermions interacting with dispersion-less phonons by using a recently developed projector-based renormalization method (PRM). At half-filling the system shows a metal-insulator transition to a Peierls distorted state at a critical electron-phonon coupling where both phases are described within the same theoretical framework. The transition is accompanied by a phonon softening at the Brillouin zone boundary and a gap in the electronic spectrum. For different filling, the phonon softening appears away from the Brillouin zone boundary and thus reflects a different type of broken symmetry state.

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S. Sykora, A. Huebsch, K. W. Becker. 2006-05-25. Analytical approach to the quantum-phase transition in the one-dimensional spinless Holstein model. https://doi.org/10.1140/epjb%2Fe2006-00211-1

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