The dynamics of ultracold atoms in light-induced synthetic gauge fields

Abraham J. Olson

Published Jan 1, 2015• 0 citations

Abstract

A central aim of this research is to study the dynamics of ultracold atoms in synthetic gauge fields. In this work, we developed a method to optimize the evaporation of ultracold atoms to the Bose-Einstein condensate (BEC) phase. We implement a model of atomic evaporation in a trapping potential, and we find optimal parameters for the trap depth and stiffness during evaporation. Using this model, we achieve a high efficiency of optical evaporation (γ eff = 4.0). Using that BEC, we study the dynamics of the BEC in various light-induced synthetic gauge fields. In particular, we have studied the transition between adiabatic and diabatic transport in a spin-orbit (SO) coupled BEC, and found the behavior to be well understood by the Landau-Zener (LZ) theory. Various parameters of the SO coupled BEC were explored, and we demonstrated the ability to use such LZ transitions as the basis of an atomic transistor. Finally, we created a novel type of 3π spin-orbit coupling for ultracold atoms using modulated Raman coupling. Using the 3π SO coupling eigenlevel structure, we observed a Stueckelberg type interference of the BEC. We developed a model of Stueckelberg type interferometers, and we were able to quantitatively account for the observed interference fringes.

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