Charge and spin correlations of a Peierls insulator after a quench

TL;DR

This paper uses an exact quantum Monte Carlo method to study how charge and spin correlations evolve over time in a Peierls insulator after a sudden change in the Hamiltonian, providing insights relevant for experiments with cold atoms.

Contribution

It introduces a sign-problem-free, exact quantum Monte Carlo approach to analyze real-time charge and spin dynamics in a Peierls insulator post-quench.

Findings

Time-dependent charge and spin correlations are characterized after the quench.

Results serve as benchmarks for more complex models and experimental setups.

The method fully accounts for quantum phonon effects without Hilbert space truncation.

Abstract

Electron-phonon coupling plays a central role for time-dependent phenomena in condensed matter, for example in photo-excitation experiments. We use the continuous-time quantum Monte Carlo method to study the real-time evolution of charge and spin correlation functions of a Peierls insulator after a quench to a noninteracting Hamiltonian. This approach gives exact results, and fully takes into account quantum phonon effects without relying on a Hilbert space truncation. It is also free from a dynamical sign problem. The observed time dependence is compared to free-fermion time evolution starting from a dimerized state. Our exact results provide a benchmark for more realistic calculations, and may be directly applicable to experiments with cold atoms or trapped ions.