Dynamic stability and manipulation of bright matter-wave solitons by optical lattices in Bose-Einstein condensates

An extended variation approach to describing the dynamic evolution of self-attractive Bose-Einstein condensates is developed. We consider bright matter-wave solitons in the presence of a parabolic magnetic potential and a timespace periodic optical lattice. The dynamics of condensates is shown to be well approximated by four coupled nonlinear differential equations. A noteworthy feature is that the extended variation approach gives a critical strength ratio to support multiple stable lattice sites for the condensate. We further examine the existence of the solitons and their stabilities at the multiple stable lattice sites. In this case, the analytical predictions of Bose-Einstein condensates variational dynamics are found to be in good agreement with numerical simulations. We then find a stable region for successful manipulating matter-wave solitons without collapse, which are dragged from an initial stationary to a prescribed position by a moving periodic optical lattice.

Vortical Solitons of Three-Dimensional Bose-Einstein Condensates under Both a Bichromatic Optical Lattice and Anharmonic Potentials

We study Bose–Einstein condensate vortical solitons under both a bichromatic optical lattice and anharmonic potential.The vortical solitons are built in the form of a layer-chain structure made up of two fundamental vortices along the bichromatic optical lattice direction,which have not been reported before in the three-dimensional Bose–Einstein condensate.A variation approach is applied to find the optimum initial solutions of vortical solitons.The stabilities of the vortical solitons are confirmed by the numerical simulation of the time-dependent Gross–Pitaevskii equation.In particular,stable Bose–Einstein condensate vortical solitons with fundamental vortices of different atomic numbers in the external potential within a range of experimentally achievable timescales are found.We further manipulate the vortical solitons to an arbitrary position by steadily moving the bichromatic optical lattice,and find a stable region for the successful manipulation of vortical solitons without collapse.These results provide insight into controlling and manipulating the Bose–Einstein condensate vortical solitons for macroscopic quantum applications.