Hydrodynamics of the interacting Bose gas in the Quantum Newton Cradle setup

摘要: Describing and understanding the motion of quantum gases out equilibrium is one most important modern challenges for theorists. In groundbreaking Quantum Newton Cradle experiment [Kinoshita, Wenger Weiss, Nature 440, 900, 2006], quasi-one-dimensional cold atom were observed with unprecedented accuracy, providing impetus many developments on effects low dimensionality in out-of-equilibrium physics. But it only recently that theory generalized hydrodynamics has provided adequate tools a numerically efficient description. Using it, we give complete numerical study time evolution an ultracold atomic gas this setup, interacting parameter regime close to original experiment. We evaluate full evolving phase-space distribution particles. simulate oscillations due harmonic trap, collision clouds without thermalization, observe small elongation actual oscillation period cloud deformations many-body dephasing. also analyze weak anharmonicity. experiment, measurements are made after release from one-dimensional trap. density curves such release, characterizing necessary reaching asymptotic state where integrable quasi-particle momentum function emerges.