2002/12/04 by B. B. Baizakov, B B Baizakov, V. V. Konotop +3 · 4 citations
Physics and Astronomy · #Bose–Einstein condensate #Brillouin scattering #Brillouin zone #Cold Atom Physics and Bose-Einstein Condensates #Function (biology) #Instability #Modulational instability #Nonlinear Photonic Systems #Stability (learning theory) #Strong Light-Matter Interactions #cond-mat.soft #nlin.PS
paper · pdf · doi:10.1088/0953-4075/35/24/312
published as J. Phys. B 35, 5105 (2002) · 17 pages, 13 figures
openalex publication_date 2002/12/04 · arxiv created 2003/06/25 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We show that the phenomenon of modulational instability in arrays of Bose–Einstein condensates confined to optical lattices gives rise to coherent spatial structures of localized excitations. These excitations represent thin discs in 1D, narrow tubes in 2D, and small hollows in 3D arrays, filled in with condensed atoms of much greater density compared to surrounding array sites. Aspects of the developed pattern depend on the initial distribution function of the condensate over the optical lattice, corresponding to particular points of the Brillouin zone. The long-time behaviour of the spatial structures emerging due to modulational instability is characterized by the periodic recurrence to the initial low-density state in a finite optical lattice. We propose a simple way to retain the localized spatial structures with high atomic concentration, which may be of interest for applications. A theoretical model, based on the multiple-scale expansion, describes the basic features of the phenomenon. Results of numerical simulations confirm the analytical predictions.