Nonequilibrium Steady States and Resonant Tunneling in Time-Periodically Driven Systems with Interactions

TL;DR

This paper investigates heating and steady states in strongly correlated, periodically driven systems using Floquet dynamical mean-field theory, revealing resonant tunneling effects and control mechanisms for Floquet state populations.

Contribution

It introduces a detailed analysis of non-equilibrium steady states in strongly interacting systems under periodic driving, highlighting resonant tunneling's role and control strategies for Floquet states.

Findings

Resonant tunneling significantly influences heating in driven kinetic energy systems.

Resonant tunneling can be exploited to control Floquet state populations, enabling photo-doping.

Strong modulation of double occupancy occurs with oscillating magnetic fields near Feshbach resonances.

Abstract

Time-periodically driven systems are a versatile toolbox for realizing interesting effective Hamiltonians. Heating, caused by excitations to high-energy states, is a challenge for experiments. While most setups address the relatively weakly-interacting regime so far, it is of general interest to study heating in strongly correlated systems. Using Floquet dynamical mean-field theory, we study non-equilibrium steady states (NESS) in the Falicov-Kimball model, with time-periodically driven kinetic energy or interaction. We systematically investigate the nonequilibrium properties of the NESS. For a driven kinetic energy, we show that resonant tunneling, where the interaction is an integer multiple of the driving frequency, plays an important role in the heating. In the strongly correlated regime, we show that this can be well understood using Fermi\textquoteright s golden rule and the Schrieffer-Wolff transformation for a time-periodically driven system. We furthermore demonstrate that resonant tunneling can be used to control the population of Floquet states to achieve "photo-doping". For driven interactions introduced by an oscillating magnetic field near a Feshbach resonance widely adopted, we find that the double occupancy is strongly modulated. Our calculations apply to shaken ultracold atom systems, and to solid state systems in a spatially uniform but time-dependent electric field. They are also closely related to lattice modulation spectroscopy. Our calculations are helpful to understand the latest experiments on strongly correlated Floquet systems.