Generating soliton trains through Floquet engineering

TL;DR

This paper demonstrates how Floquet engineering via lattice shaking can reliably generate and control soliton trains in ultracold bosonic gases trapped in optical lattices, offering a stable method for soliton preparation.

Contribution

It introduces a Floquet-based technique to convert the ground state of a cold atom system into a train of solitons by inverting hopping energy sign through rapid lattice shaking.

Findings

Number of solitons depends on nonlinearity and trap curvature

Technique works in both high and low frequency regimes

System remains stable against noise

Abstract

We study a gas of interacting ultracold bosons held in a parabolic trap in the presence of an optical lattice potential. Treating the system as a discretised Gross-Pitaevskii model, we show how Floquet engineering, by rapidly ``shaking'' the lattice, allows the ground-state of the system to be converted into a train of bright solitons by inverting the sign of the hopping energy. We study how the number of solitons produced depends on the system's nonlinearity and the curvature of the trap, show how the technique can be applied both in the high and low driving-frequency regimes, and demonstrate the phenomenon's stability against noise. We conclude that the Floquet approach is a useful and stable method of preparing solitons in cold atom systems.