Chinese Physics Letters

Evolution of Matter Wave Interference of Bose-Condensed Gas in a 1D Optical Lattice

Xu Zhi-Jun, Dongmei Zhang

Published Aug 23, 2007• 0 citations

Abstract

For a Bose-condensed gas in a combined potential consisting of an axially-symmetric harmonic magnetic trap and one-dimensional (1D) optical lattice, using the mean-field Gross–Pitaevskii (G-P) equation and the propagator method, we obtain the analytical result of the order parameter for matter wave interference at any time. The evolution of the interference pattern under a variation of the relative phase Δϕ between successive subcondensates trapped on an optical lattices is also studied. For Δϕ = π, the interference pattern is symmetric with two sharp peaks, which are symmetrically located on a straight line on both sides of a vacant central peak and moving apart from each other. This work is in agreement with available experimental results.

DOI: 10.1088/0256-307x/24/9/009

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