Nonlinear intraband tunneling of BEC in a cubic three-dimensional lattice

Abstract

The intra-band tunneling of a Bose-Einstein condensate between three degenerate high-symmetry X-points of the Brillouin zone of a cubic optical lattice is studied in the quantum regime by reduction to a three-mode model. The mean-field approximation of the deduced model is described. Compared to the previously reported two-dimensional (2D) case [Phys. Rev. A 75, 063628 (2007)], which is reducible to the two-mode model, in the case under consideration there exist a number of new stable stationary atomic distributions between the X-points and a new critical lattice parameter. The quantum collapses and revivals of the atomic population dynamics are absent for the experimentally realizable time span. The 2D stationary configurations, embedded into the 3D lattice, turn out to be always unstable, while existence of a stable 1D distribution, where all atoms populate only one X-state, may serve as a starting point in the experimental study of the nonlinear tunneling in the 3D lattice.

arXiv comment13 pages, 10 figures, accepted to PRA

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Cited by in corpus (5)

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• Tunneling-induced damping of phase coherence revivals in deep optical lattices
• Quantum switching at a mean-field instability of a Bose-Einstein condensate in an optical lattice
• Accelerating many-body entanglement generation by dipolar interactions in the Bose-Hubbard model
• Mesoscopic quantum switching of a Bose-Einstein condensate in an optical lattice governed by the parity of the number of atoms