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Dispersion control for matter waves and gap solitons in optical superlattices

Pearl J. Y. Louis·Elena A. Ostrovskaya·Yuri S. Kivshar
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Abstract

We present a numerical study of dispersion manipulation and formation of matter-wave gap solitons in a Bose-Einstein condensate trapped in an optical superlattice. We demonstrate a method for controlled generation of matter-wave gap solitons in a stationary lattice by using an interference pattern of two condensate wavepackets, which mimics the structure of the gap soliton near the edge of a spectral band. The efficiency of this method is compared with that of gap soliton generation in a moving lattice recently demonstrated experimentally by Eiermann et al. [Phys. Rev. Lett. 92, 230401 (2004)]. We show that, by changing the relative depths of the superlattice wells, one can fine-tune the effective dispersion of the matter waves at the edges of the mini-gaps of the superlattice Bloch-wave spectrum and therefore effectively control both the peak density and the spatial width of the emerging gap solitons.

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Pearl J. Y. Louis, Elena A. Ostrovskaya, Yuri S. Kivshar. 2004-11-19. Dispersion control for matter waves and gap solitons in optical superlattices. https://doi.org/10.1103/physreva.71.023612

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