Kevin C Wright, Joint Quantum Institute, University of Maryland

Topic: "Phase slips and weak links: Superfluidity in a rotating "circuit" of ultra-cold atoms"  (Video)

Abstract: Quantum fluids often exhibit remarkable properties such as long-range coherence and superfluidity. These properties can make them useful for constructing sensors and other devices. Liquid helium and superconductors are the traditional laboratory systems in which macroscopic quantum phenomena have been studied. More recently, ultra-cold atomic gases have been shown to exhibit similar behavior, including superfluidity. The versatility and new degrees of control allowed by ultra-cold atomic gases make them an ideal system for a new generation of experiments involving superfluidity and other macroscopic quantum effects. Many of these phenomena are particularly apparent in a ring geometry, because of the quantization of circulation around a closed path. I will present the results of recent experiments manipulating persistent currents in a ring-shaped atomic Bose-Einstein condensate with a rotating “weak link”. Prospects for using SQUID-like atom “circuits” for rotation sensing, and as a means for investigating the exotic properties of macroscopic quantum systems will also be discussed.