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

Institut für Theoretische Physik und Astrophysik, Universität Würzburg, 97074 Würzburg, Germany.
Physical Review Letters (Impact Factor: 7.73). 05/2012; 109(11). DOI: 10.1103/PhysRevLett.109.116407
Source: arXiv

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.

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