Floquet prethermalization in the resonantly driven Hubbard model

TL;DR

This paper investigates long-lived prethermalized states in the driven Hubbard model, revealing how periodic driving creates nonthermal states with specific properties, and introduces a method to approximate correlation effects via an effective Hamiltonian.

Contribution

It demonstrates the existence of Floquet prethermalization in the resonantly driven Hubbard model and proposes a numerical approach to model correlation effects from higher-order corrections.

Findings

Prethermal states exhibit nonzero current and specific effective temperatures.

Double occupation dynamics are well-described by the effective Hamiltonian.

Prethermalization plateaus are influenced by high-frequency expansion corrections.

Abstract

We demonstrate the existence of long-lived prethermalized states in the Mott insulating Hubbard model driven by periodic electric fields. These states, which also exist in the resonantly driven case with a large density of photo-induced doublons and holons, are characterized by a nonzero current and an effective temperature of the doublons and holons which depends sensitively on the driving condition. Focusing on the specific case of resonantly driven models whose effective time-independent Hamiltonian in the high-frequency driving limit corresponds to noninteracting fermions, we show that the time evolution of the double occupation can be reproduced by the effective Hamiltonian, and that the prethermalization plateaus at finite driving frequency are controlled by the next-to-leading order correction in the high-frequency expansion of the effective Hamiltonian. We propose a numerical procedure to determine an effective Hubbard interaction that mimics the correlation effects induced by these higher order terms.