Slow quench dynamics of periodically driven quantum gases

TL;DR

This paper investigates the slow evolution of bosonic quantum gases in periodically driven optical lattices across different frequency regimes, revealing energy absorption phenomena and the impact of driving on effective tunneling properties.

Contribution

It provides a comparative analysis of low and high frequency driving effects, including energy absorption and the role of effective Hamiltonians in quantum state evolution.

Findings

Resonant energy absorption at low frequencies.

Driving-induced changes in tunneling amplitude and sign.

Time scales for adiabatic following of the ground state.

Abstract

We study the evolution of bosons in a periodically driven optical lattice during a slow change of the driving amplitude. Both the regime of high frequency and low frequency driving are investigated. In the low frequency regime, resonant absorption of energy is observed. In the high frequency regime, the dynamics is compared to a system with an effective Hamiltonian in which the atoms are `dressed' by the driving field. This `dressing' can dramatically change the amplitude and sign of the effective tunneling. A particular focus of this study is the investigation of the time-scales necessary for the evolving quantum state to follow almost adiabatically to the ground-state of the effective many body system.