Exciting Bose-Condensate using oscillatory fields: Observation of turbulence and fragmentation

In this work we demonstrate nucleation of vortices in a BEC, where an oscillating field generated by a set of coils is superimposed to the trapping field creating displacement, rotation and deformation of the trap potential. As a function of the amplitude of oscillation we observe several different behaviors of the condensate cloud allowing the construction of a diagram for stable structures. Increasing the amplitude we observe the formation of one, two, three or more vortices in the cloud. Above certain amplitude of oscillation we observe uncountable vortices in every direction, producing a tangled vortices configuration which can be considered as the emergence of a turbulent regime in the cloud. Variations of behavior during TOF for the cloud seem to be a signature of the turbulent regime. In extremes conditions of oscillations, a fragmentation of the cloud is observed. A theoretical model for the fragmentation is offered. .