Shortcuts to adiabaticity for trapped ultracold gases

JEAN-FRANCOIS SCHAFF; PABLO CAPUZZI; GUILLAUME LABEYRIE; PATRIZIA VIGNOLO

NEW JOURNAL OF PHYSICS

IOP PUBLISHING LTD

Lugar: Londres; Año: 2011 vol. 13 p. 113017 - 11301731

1367-2630

We study experimentally and theoretically the controlled transfer of harmonically trapped ultracold gases between different quantum states. In particular, we experimentally demonstrate a fast decompression and displacement of both a non-interacting gas and an interacting Bose–Einstein condensate, which are initially at equilibrium. The decompression parameters are engineered such that the final state is identical to that obtained after a perfectly adiabatic transformation despite the fact that the fast decompression is performed in the strongly non-adiabatic regime. During the transfer the atomic sample goes through strongly out-of-equilibrium states, while the external confinement is modified until the system reaches the desired stationary state. The scheme is theoretically based on the invariants of motion and scaling equation techniques and can be generalized to decompression trajectories including an arbitrary deformation of the trap. It is also directly applicable to arbitrary initial non-equilibrium states.