Mode coupling of interaction quenched ultracold few-boson ensembles in periodically driven lattices

TL;DR

This paper explores how periodic driving and interaction quenches influence the out-of-equilibrium dynamics of ultracold bosons in optical lattices, revealing resonant behaviors and mode excitations that can be controlled for future applications.

Contribution

It introduces a detailed analysis of mode coupling and resonance phenomena in driven, quenched ultracold bosonic lattices, highlighting the tunability of intra- and inter-well excitations.

Findings

Periodic driving induces out-of-phase dipole modes in outer wells.

Interaction quenches lead to mixed excitations and enhanced breathing modes.

Resonances between intra- and inter-well dynamics are tunable via driving frequency.

Abstract

The out-of-equilibrium dynamics of interaction quenched finite ultracold bosonic ensembles in periodically driven one-dimensional optical lattices is investigated. It is shown that periodic driving enforces the bosons in the outer wells of the finite lattice to exhibit out-of-phase dipole-like modes, while in the central well the atomic cloud experiences a local breathing mode. The dynamical behavior is investigated with varying driving frequency, revealing a resonant-like behavior of the intra-well dynamics. An interaction quench in the periodically driven lattice gives rise to admixtures of different excitations in the outer wells, an enhanced breathing in the center and an amplification of the tunneling dynamics. We observe then multiple resonances between the inter- and intra-well dynamics at different quench amplitudes, with the position of the resonances being tunable via the driving frequency. Our results pave the way for future investigations on the use of combined driving protocols in order to excite different inter- and intra-well modes and to subsequently control them.