arXiv:cond-mat/0312054 · Journal of Optics B Quantum and Semiclassical Optics

The dynamical generation of two-dimensional matter-wave discrete solitons

Artem M. Dudarev, Roberto B. Diener, Qian Niu

Published May 1, 2004• 14 citations

Abstract

We suggest a method to experimentally obtain two-dimensional matter-wave discrete solitons with a self-repulsive Bose–Einstein condensate in optical lattices. At the edge of the Brillouin zone, a wavepacket effective mass is negative, which could be treated as an inversion of the nonlinearity sign. Above critical nonlinearity this makes the wavepackets collapse partially into localized modes with a chemical potential located in the gap between the first and the second bands. This critical nonlinearity is also associated with the smallest nonlinearity for which the discrete solitons are possible in the gap. Extensive numerical simulations for square and asymmetric honeycomb lattices in the continuous model illustrate every stage of the process.

DOI: 10.1088/1464-4266/6/5/010

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