New experimental system to study coupled vortices in a two-species Bose-Einstein condensate 23Na-41K with tunable interactions

• Ano de defesa: 2017
• Autor(a) principal: Castilho, Patricia Christina Marques
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: Bose-Bose mixtures; Condensados girantes; Feshbach resonances; Misturas bóson-bóson; Rede de vórtices; Resonâncias de Feshbach; Rotating BEC; Stirring Beam; Técnica de stirring; Vortex lattice
• Link de acesso: http://www.teses.usp.br/teses/disponiveis/76/76131/tde-11092017-082144/

Two-component fluids can be miscible (if they overlap in space) or immiscible (if they remain phase-separated). In the context of trapped two-species Bose-Einstein condensates (BECs), these miscibility regions can only be fully characterize if one considers the interspecies interaction, the mass ratio and the number of atoms in each species. The dynamics of coupled vortices is different for each miscibility region and exotic vortices configurations (such as, square vortex lattices, \"vortex sheets\", skyrmions, etc.) are expected to occur. In this thesis, we present the construction of a new experimental system able to produce a two-species Bose-Einstein condensate of 23Na-41K atoms with tunable interspecies interactions and study the dynamics of coupled vortices in the different miscibility regimes. The BEC of sodium atoms obtained first in a Plug trap and later, in a crossed optical dipole trap, is fully characterized as well as the cold atomic cloud of potassium atoms produced by means of a Gray molasses cooling procedure. In the crossed optical dipole trap, the vortices will be nucleated with the use of a stirring beam. Therefore, in the end of this thesis, we present the stirring beam setup and its characterization prior aligning it into the 23Na BEC.