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Band structures of a dipolar Bose-Einstein condensate in one-dimensional lattices

Institute of Photonics Technologies, National Tsing-Hua University, 300, Hsinchu, Taiwan; Department of Physics, National Changhua University of Education, Taiwan; Institute of Physics, National Chiao Tung University, 300, Hsinchu, Taiwan
Physical Review A (Impact Factor: 2.99). 08/2008; 78(2). DOI: 10.1103/PhysRevA.78.023629

ABSTRACT We derive the effective Gross-Pitaevskii equation for a cigar-shaped dipolar Bose-Einstein condensate in one-dimensional lattices and investigate the band structures numerically. Due to the anisotropic and the long-ranged dipole-dipole interaction in addition to the known contact interaction, we elucidate the possibility of modifying the band structures by changing the alignment of the dipoles with the axial direction. With the considerations of the transverse parts and the practical physical parameters of a cigar-shaped trap, we show the possibility to stabilize an attractive condensate simply by adjusting the orientation angle of dipoles. Some interesting Bloch waves at several particle current densities are identified for possible experimental observations.

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