Effects induced by oscillatory excitation in atomic superfluids

Abstract

With this post-doctoral project, we intend to investigate atomic quantum fluids and their excitations by oscillating external fields. Recently, exciting a quantum fluid with periodic oscillations, we found that vortices are generated by mechanisms which are still under investigation. Depending on the frequency and amplitude of excitation, we observed that for certain times of excitement, there is a proliferation of vortices up to the point, where meandering vortices are generated, as a route to turbulence in the quantum fluid. Beyond this regime, there is a fragmentation of the superfluid. When the external field is random, the behavior is expected to be different and may evolve into a superfluid state of fragmentation, without necessarily passing through other stages. In this project we will be analyzing the experimental results when the atomic superfluid is excited by an oscillating field that evolves from a periodic situation to an excitated state with random amplitude and frequency. We intend to analyze the effects of location (Anderson location type, but in the time domain), as well as the possibility of further phases in a quantum fluid subject to such perturbations. Thermodynamic studies will also be realized. (AU)