Kyuhwan Lee

Sep 23, 2024 | link.aps.org | Sol Kim |Kyuhwan Lee |Jongmin Kim |Y. C. Shin

We present a method for producing a flat, large-area Fermi gas of Li6 with a uniform area density. The method uses a programmable optical potential within a feedback loop to flatten the in-plane trapping potential for atoms. The optical potential is generated using a laser beam, whose intensity profile is adjusted by a spatial light modulator and optimized through measurements of the density distribution of the sample.

Jul 28, 2024 | nature.com | Kyuhwan Lee |Taehoon Kim

AbstractThe Kibble–Zurek mechanism is a theoretical framework that describes the formation and scaling of topological defects in symmetry-breaking phase transitions. It was originally conceptualized for superfluid helium. The theory predicts that the number of quantum vortices should scale as a power law with the rate at which the system passes through the lambda transition, but demonstrating this effect has been elusive in experiments using superfluid systems.