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arXiv · 1205.0612

Effect of Electron-Phonon Interaction Range for a Half-Filled Band in One Dimension

Martin Hohenadler·Fakher F. Assaad·Holger Fehske
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Abstract

We demonstrate that fermion-boson models with nonlocal interactions can be simulated at finite band filling with the continuous-time quantum Monte Carlo method. We apply this method to explore the influence of the electron-phonon interaction range for a half-filled band in one dimension, covering the full range from the Holstein to the Fröhlich regime. The phase diagram contains metallic, Peierls, and phase-separated regions, which we characterize in terms of static and dynamical correlation functions. In particular, our results reveal a suppression of $2k_F$ charge correlations with increasing interaction range, allowing for a power-law decay comparable to the pairing correlations.

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Martin Hohenadler, Fakher F. Assaad, Holger Fehske. 2012-09-18. Effect of Electron-Phonon Interaction Range for a Half-Filled Band in One Dimension. https://doi.org/10.1103/physrevlett.109.116407

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