Palestrante
Descrição
Bose-Einstein condensation (BEC) is a state of matter in which all the atoms of the system are in the same quantum state, the lowest energy state. This state of matter starts to exist once a dilute gas of bosons is cooled down to very low temperatures of the order of absolute zero. It was predicted by Albert Einstein when using Bose statistics in the middle of the 1920’s but it was only experimentally achieved by Eric Cornell in 1995. In his experiment Cornell was able to obtain a diluted system in ultra-cold temperatures because he was using alkaline gases which have a weak inter-atomic interaction and this achievement gave him the Nobel Prize. Since this date up to now the study of ultracold atoms have become an area of great interest in physics. There has been a great advance in the study of BEC with experimental techniques that physicists made to understand the nature behind this so important phenomenon, e.g. the study of disorder in BEC’s, studies of Anderson localization, realization of new exotic systems like quantum droplets etc. One experiment which is of great importance in this work is the bubble trap. One of the ways the bubble can be produced is using a radiofrequency field in an adiabatic potential based on a quadrupolar magnetic trap. This experimental setup allows the production of superfluid currents on a ring shaped geometry both with the creation of persistent currents around the bubble or with the development of nonharmonic confinement in a rotating gas to prevent them from escaping. Either way what we have is a superfluid of BEC with a hole on the interior which characterizes a quantum vortex. Quantum vortices are the cornerstone of the superfluids. They differ from classical vortices because they have a quantized flow. The rotation of the superfluid is characterized by the fact that it’s density is zero at a singular point.(1-2) The behavior of vortices in relation to physical parameters still presents challenges in regard to the theoretical description, in special to the case of the BEC on the bubble trap. The main goal of this work is to produce a better theoretical understanding of quantum vortices phenomenon in bubble traps. We plan to use variational analytical methods with the Gross-Pitaevskii’s functional in conjunction with real-time three-dimensional long-scale simulations (3) to study these vortices on the bubble trap BEC. In this way, we seek to contribute with a robust theoretical base in a cutting-edge field that maintains significant contact with current experiments.
Referências
1 SANTOS, F. E. A. Hydrodynamics of vortices in Bose-Einstein condensates: a defect-gauge field approach. Physical Review A, v. 94, n.6,p.063633, 2016.
2 TSATSOS, M. C. et. al. Quantum turbulence in trapped atomic Bose-Einstein condensates. Physics Reports, v.622, p.1-52, 2016.doi: 10.1016/j.physrep.2016.02.003 .
3 CIDRIM, A. et al. Vortices in self-bound dipolar droplets. Physical Review A,v.98, p.023618,2018.
doi:10.1103/PhysRevA.98.023618.
| Subárea | Física Atômica e Molecular |
|---|---|
| Apresentação do trabalho acadêmico para o público geral | Sim |
