CONTROL OF MATTER WAVES IN OPTICAL LATTICES BY FESHBACH RESONANCE

摘要

Using the Feahbach resonance (FR) one can change a scattering length of two-body interactions and thus affect nonlinear dynamics of excitations in a Bose-Einstein condensate. The phenomenon is described by the Gross-Pitaevskii (GP) equation with varying nonlinearity. In this work we discuss the effect of variation of the nonlinearity on excitations in a BEG placed in an optical lattice. More specifically, we describe reductions of a three-dimensional (3D) GP equation to a ID perturbed nonlinear Schrodinger (NLS) equation for different relations among parameters; discuss periodic solutions of the NLS equation; carry out numerical study of the dynamics of the NLS equation with a periodic and parabolic trap potentials. Special attention is paid to the process of generation of trains of bright and dark matter solitons from initially periodic waves.