Title: Floquet prethermalization in the resonantly driven Hubbard model,
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.