# Dominant charge-density-wave correlations in the Holstein model on the half-filled square lattice

## TL;DR

This study uses quantum Monte Carlo simulations to investigate charge-density-wave correlations in the Holstein model on a half-filled square lattice, finding strong CDW tendencies across various phonon frequencies.

## Contribution

It provides the first comprehensive analysis across all phonon frequencies, demonstrating persistent CDW correlations in the Holstein model at zero temperature.

## Key findings

- CDW correlations dominate over pairing correlations at low temperatures
- Results are consistent with a CDW ground state
- Analysis spans adiabatic to antiadiabatic limits

## Abstract

We use an unbiased, continuous-time quantum Monte Carlo method to address the possibility of a zero-temperature phase without charge-density-wave (CDW) order in the Holstein and, by extension, the Holstein-Hubbard model on the half-filled square lattice. In particular, we present results spanning the whole range of phonon frequencies, allowing us to use the well understood adiabatic and antiadiabatic limits as reference points. For all parameters considered, our data suggest that CDW correlations are stronger than pairing correlations even at very low temperatures. These findings are compatible with a CDW ground state that is also suggested by theoretical arguments.