Expansion of a Bose-Einstein condensate formed on a joint harmonic and one-dimensional optical-lattice potentials

TL;DR

This paper investigates the expansion dynamics of a Bose-Einstein condensate in combined optical-lattice and harmonic potentials, using numerical simulations that align well with existing experimental results.

Contribution

It provides a detailed numerical analysis of condensate expansion in combined potentials, confirming experimental observations and enhancing understanding of BEC behavior in complex trapping environments.

Findings

Numerical results agree with experiments on axial and radial expansion sizes.

Oscillation and revival of interference patterns match experimental observations.

Expansion behavior under different potentials is characterized and validated.

Abstract

We study the expansion of a Bose-Einstein condensate trapped in a combined optical-lattice and axially-symmetric harmonic potentials using the numerical solution of the mean-field Gross-Pitaevskii equation. First, we consider the expansion of such a condensate under the action of the optical-lattice potential alone. In this case the result of numerical simulation for the axial and radial sizes during expansion is in agreement with two experiments by Morsch et al.[2002 Phys. Rev. A 66 021601(R) and 2003 Laser Phys. 13 594]. Finally, we consider the expansion under the action of the harmonic potential alone. In this case the oscillation and the disappearance and revival of the resultant interference pattern is in agreement with the experiment by M\"uller et al. [2003 J. Opt. B 5 538].