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

Tarun Kanti Ghosh·K. Machida
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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.

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Tarun Kanti Ghosh, K. Machida. 2005-10-05. Multibranch Bogoliubov-Bloch spectrum of a cigar shaped Bose condensate in an optical lattice. https://doi.org/10.1103/physreva.72.053623

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