Gaussian trajectory description of fragmentation in an isolated spinor condensate

Spin-1 Bose gases quenched to spin degeneracy exhibit fragmentation: the appearance of a condensate in more than one single-particle state. Due to its highly entangled nature, the dynamics leading to this collective state are beyond the scope of a Gaussian variational approximation of the many-body wave function. Here, we improve the performance of the Gaussian variational ansatz by considering dissipation into a fictitious environment, effectively suppressing entanglement within individual quantum trajectories at the expense of introducing a classical mixture of states. We find that this quantum trajectory approach captures the dynamical formation of a fragmented condensate and analyze how much dissipation should be added to the experiment in order to keep a single realization in a nonfragmented state.

Publication year:2022

Keywords:A1 Journal article

Accessibility:Open