Nonclassical dynamics of Bose-Einstein condensates in an optical lattice in the superfluid regime
Year: 2007
Authors: Franzosi R.
Autors Affiliation: Dipartimento di Fisica, Università di Firenze
CNR-INFM, Via Sansone 1, I-50019 Sesto Fiorentino, Italy
Abstract: A condensate in an optical lattice, prepared in the ground state of the superfluid regime, is stimulated first by suddenly increasing the optical lattice amplitude and then, after a waiting time, by abruptly decreasing this amplitude to its initial value. Thus the system is first taken to the Mott regime and then back to the initial superfluid regime. We show that, as a consequence of this nonadiabatic process, the system falls into a configuration far from equilibrium whose superfluid order parameter is described in terms of a particular superposition of Glauber coherent states that we derive. We also show that the classical equations of motion describing the time evolution of this system are inequivalent to the standard discrete nonlinear Schrodinger equations. By numerically integrating such equations with several initial conditions, we show that the system loses coherence, becoming insulating.
Journal/Review: PHYSICAL REVIEW A
Volume: 75 (5) Pages from: 053610-1 to: 053610-5
KeyWords: Equations of motion; Ground state; Optical properties; Schrodinger equation, Nonadiabatic process; Optical lattice; Superfluid regime, Bose-Einstein condensationDOI: 10.1103/PhysRevA.75.053610Citations: 3data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2024-11-17References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here