arXiv:cond-mat/0312124 · Journal of Physics B Atomic Molecular and Optical Physics

Stability of small-amplitude normal modes of a Bose–Einstein condensate with a singly quantized vortex confined in an optical lattice

Aranya B. Bhattacherjee, O. Morsch, E. Arimondo

Published May 18, 2004• 15 citations

Abstract

We study the dynamics of a BEC with a singly quantized vortex, placed in the combined potential of a 1D (2D) optical lattice and an axi-symmetric harmonic trap. A time-dependent variational Lagrangian analysis shows that an optical lattice helps to stabilize the vortex which in the absence of the optical lattice is unstable. We find that the normal modes are stable only if the depth of the optical potential is more than a certain critical value. This critical value of the optical potential depends on the 2D interaction parameter. In general, the higher the interaction parameter, the lower the value of the optical potential required to stabilize the vortex. The BEC with the singly quantized vortex is found to be relatively more unstable in a 2D optical lattice compared to a 1D optical lattice.

DOI: 10.1088/0953-4075/37/11/012

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