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

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 Fr\"ohlich 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.