| Bose-Einstein condensation(BEC)as a macroscopical quantum mechanics phenomenon,which was predicted by theory and then confirmed by experiment,has been a popular research area.BEC has been a hot research target or tool in many fields because of its good quantum coherence,among which construct the potential by light or magnetism to accurately manipulate BEC is an essential way.BEC in a double well is a very typical simulation system to study the resembled superconductivity Josephson effect.So typical Josephson effects,like quantum tunneling between two wells and self-trapping phenomenon can be exhibited by modulating the magnetism of double well or change the magnitude of the interaction between BEC atoms by Fechbach resonance method.We propose a new approach to control the dynamics of atomic Bose-Einstein condensates in double-well traps through changing the effective mass of atomic BEC by optical lattice.we deduce the dynamics equation in the mean-field approximation.Numerical simulation shows that the dynamics of BEC in double well changes from harmonic oscillation dominating by quantum tunneling to self-trapping effect dominating by atomic collision when we change the effective mass.And we show this transition can be explained by the altering of system energy.We also study the situation of negative effective mass and find that it can be used to simulate the kinetics of BEC of negative scattering length.Compared to adjusting double well by magnetism or atomic interaction by Fechbach resonance,this is beneficial for some requirement like fixed trapping condition or atoms not sensitive to magnetism. |
