Physical Review A
Rectified motion of a Bose-Einstein condensate in a horizontally vibrating shallow optical lattice
Yousef Azizi, Alireza Valizadeh
Abstract
We consider a Bose-Einstein condensate, described by the Gross-Pitaevskii equation, in a horizontally vibrating shallow optical lattice. We study the dynamics of a bright soliton using the collective coordinate approximation. We show that depending on the parameters, amplitude, and frequency of the vibration of the lattice, the phase space of the equation of motion for the soliton center of mass shows multistability. In the frequency locked regions, in which the soliton has a nonzero average velocity determined by the external frequency, the motion is quasiperiodic, and between the locked regions the soliton moves chaotically.