Generation of ring dark solitons by phase engineering and their oscillations in spin-1 Bose-Einstein condensates

The ring dark solitons in spin-1 $^{23}$Na and $^{87}$Rb Bose-Einstein condensates are studied numerically in the framework of the time-dependent Gross-Pitaevskii equations. By simulating the phase engineering technique in real experiments, we explore the roles of the parameters characterizing the far-off resonant laser pulse which can be used to generate the ring dark solitons. The variations of these parameters have dramatic effect on the lifetime and the decay profiles of the ring dark solitons. If only one ring dark soliton is generated in one component of the condensate, ring dark solitons in other components are inclined to be induced, resulting in a coexistence state composed of interdependent ring dark solitons coming from different components of the condensate. Ring dark solitons in this coexistence state exhibit dynamical oscillations for hundreds of milliseconds. By studying the lifetime and decaying profiles of ring dark solitons, we explore the similarities and differences of $^{23}$Na and $^{87}$Rb condensates. Besides, taking into account the fact that the center of the ring may not be coincide with that of the trap, we study the dynamics and decaying profiles of the off-centered ring dark solitons in the presence of symmetry breaking effect.