Abstract:The statics characteristics of two coupled Bose-Einstein condensate (BEC) dark solitons trapped in an optical lattice are investigated with the variational approach. It is found that the interaction between a ‘kink’ and an ‘anti-kink’ with opposite phase gradients is effectively repulsive, and the optical lattice can be controllably used to produce a pair of static BEC dark solitons. Its effect depends on the initial location of the BEC dark solitons, the lattice amplitude and wave number. Supported by the Science and Technology Program of Education Department of Hubei Province under Grant No. B20052202, and the Fund of Natural Science of Hubei Province under Grant No. 2004ABA112.