Abstract
We study the quenched dynamics of the momentum distribution of a unitary Bose gas under isotropic harmonic confinement within a time-dependent density functional approach based on our recently calculated Monte Carlo bulk equation of state. In our calculations the inter-atomic s-wave scattering length of the trapped bosons is suddenly increased to a very large value and the real-time evolution of the system is studied. Prompted by the very recent experimental data of 85Rb atoms at unitarity (Makotyn et al. in Nat Phys 10:116, 2014) we focus on the momentum distribution as a function of time. Our results suggest that at low momenta, a quasi-stationary momentum distribution is reached after a long transient, contrary to what found experimentally for large momenta which equilibrate on a time scale shorter than the one for three body losses.
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Ancilotto, F., Rossi, M., Salasnich, L. et al. Quenched Dynamics of the Momentum Distribution of the Unitary Bose Gas. Few-Body Syst 56, 801–807 (2015). https://doi.org/10.1007/s00601-015-0971-2
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DOI: https://doi.org/10.1007/s00601-015-0971-2