Transport and Turbulence in Quasi-Uniform and Versatile Bose-Einstein Condensates / Springer Theses (PDF)

Advancing the experimental study of superfluids relies on increasingly sophisticated techniques. This work develops and demonstrates the loading of Bose-Einstein condensates (BECs) into nearly arbitrary trapping potentials, with a resolution improved by a factor of seven when compared to reported systems. These advanced control techniques have now been adopted by several cold atoms labs around the world.

The book describes how this BEC system was used to study 2D superfluid dynamic. In particular, negative temperature vortex states in a two-dimensional quantum fluid were observed. These states were first predicted by Lars Onsager 70 years ago and have significance to 2D turbulence in quantum and classical fluids, long-range interacting systems, and defect dynamics in high-energy physics. These experiments have established dilute-gas BECs as the prototypical system for the experimental study of point vortices and their nonequilibrium dynamics.

Also presented is a new approach to superfluid circuitry based on classical acoustic circuits, whose conceptual and quantitative superiority over previous lumped-element models is demonstrated. This approach has established foundational principles of superfluid circuitry that will impact the design of future transport experiments and new generation quantum devices, such as atomtronics circuits and superfluid sensors.