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arXiv · 2209.05498

The one-dimensional Holstein model revisited

Sijia Zhao·Zhaoyu Han·Ilya Esterlis·Steven A. Kivelson
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Abstract

We analyze the global ground-state (quantum) phase diagram of the one-dimensional Holstein model at half-filling as a function of the strength of the electron-phonon coupling (represented by the strength of the phonon-induced attraction, $U$) and the phonon frequency, $\omega_0$. In addition to reanalyzing the various asymptotic regimes, we have carried out density-matrix renormalization group simulations to correct previous inferences concerning the anti-adiabatic (large $\omega_0$) and strong coupling (large $U$) regimes. There are two distinct phases - a fully gapped commensurate charge-density-wave and a spin-gapped Luther-Emery phase with a gapless charge mode - separated by a phase boundary, with a shape that reflects different microscopic physics in the weak and strong coupling limits.

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Sijia Zhao, Zhaoyu Han, Ilya Esterlis, Steven A. Kivelson. 2022-09-12. The one-dimensional Holstein model revisited. https://doi.org/10.1103/physrevb.107.075142

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