arXiv:cond-mat/0510096 · Physical Review A

Multibranch Bogoliubov-Bloch spectrum of a cigar-shaped Bose condensate in an optical lattice

Tarun Kanti Ghosh, K. Machida

Published Nov 18, 2005• 6 citations

Abstract

We study properties of excited states of an array of weakly coupled quasi-two-dimensional Bose condensates by using the hydrodynamic theory. The spectrum of the axial excited states strongly depends on the coupling among the various discrete radial modes in a given symmetry. By including mode coupling within a given symmetry, the complete excitation spectrum of axial quasiparticles with various discrete radial nodes are presented. A single parameter which determines the strength of the mode coupling is identified. The excitation spectrum in the zero angular momentum sector can be observed by using the Bragg scattering experiments.

DOI: 10.1103/physreva.72.053623

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