Non-equilibrium dynamics of quasi-one- and two-dimensional Bose gases in an optical box*

Atomic quantum gases confined in a box potential provide a versatile platform for studying non-equilibrium dynamics. In this poster, we explore different quench-induced dynamics under two scenarios. Firstly, we investigate the collapse dynamics of a quantum vortex in a two-dimensional atomic superfluid following a rapid interaction ramp from repulsion to attraction. We identify the conditions and time scales for a superfluid vortex to radially converge into a quasi-stationary vortex soliton-like density profile. Additionally, we observe emergent self-similar dynamics in the density perturbations caused by azimuthal modulational instability, leading to the eventual splitting of a solitonic ring profile or direct fragmentation of a superfluid into disordered, yet roughly circular arrays of Townes soliton-like wavepackets. Secondly, we examine the density and phase correlation dynamics in quasi-one-dimensional attractive Bose gases upon an interaction quench. Our experiment reveals an interplay between modulational instability seeded from bulk fluctuations and shockwaves emitted from an effective edge-induced dam-break. We also report on how long-range order can be re-established following an interaction quench back to the repulsive regime.