Citation:
Torrontegui, E., Chen, X., Modugno, M., Ruschhaupt, A., Guéry-Odelin, D., Muga, J. G. (2012). Fast transitionless expansion of cold atoms in optical Gaussian-beam traps. Physical Review A, 85(3).
Sponsor:
We thank G. C. Hegerfeldt for useful discussions. We acknowledge funding by the Basque government (Grant No. IT472-10), Ministerio de Ciencia e Innovación (Grant No. FIS2009-12773-C02-01), and the UPV/EHU under program UFI 11/55. X.C. thanks the Juan de la Cierva Programme, the National Natural Science Foundation of China (Grants No. 60806041 and No. 61176118), and the Shanghai Leading Academic Discipline Program (Grant No. S30105); E.T. thanks the Basque government (Grant No. BFI08.151); and D.G.O. thanks the Agence National de la Recherche, the Région Midi-Pyrénées, University Paul Sabatier (OMASYC project), and the Institut Universitaire de France.
We study fast expansions of cold atoms in a three-dimensional Gaussian-beam optical trap. Three different methods to avoid final motional excitation are compared: inverse engineering using Lewis-Riesenfeld invariants, which provides the best overall performancWe study fast expansions of cold atoms in a three-dimensional Gaussian-beam optical trap. Three different methods to avoid final motional excitation are compared: inverse engineering using Lewis-Riesenfeld invariants, which provides the best overall performance, a bang-bang approach, and a fast adiabatic approach. We analyze the excitation effect of anharmonic terms, radial-longitudinal coupling, and radial-frequency mismatch. In the inverse-engineering approach these perturbations can be suppressed or mitigated by increasing the laser beam waist.[+][-]