Interaction-Assisted Quantum Tunneling of a Bose-Einstein Condensate Out of a Single Trapping Well (original) (raw)
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An essentially-exact approach to compute the wavefunction in the time-dependent many-boson Schrödinger equation is derived and employed to study accurately the process of splitting a trapped condensate when ramping-up a barrier such that a double-well is formed. We follow the role played by many-body excited states during the splitting process. Among others, a 'counter-intuitive' regime is found in which the evolution of the condensate when the barrier is ramped-up sufficiently slow is not to the ground-state which is a fragmented condensate, but to a low-lying excited-state which is a coherent condensate. Experimental implications are discussed.