In the expanding universe, relativistic scalar fields are thought to be attenuated by “Hubble friction,” which results from the dilation of the underlying spacetime metric. By contrast, in a contracting universe this pseudofriction would lead to amplification. Here, we experimentally …

Accurate Determination of Hubble Attenuation and Amplification in Expanding and Contracting Cold-Atom Universes Read more »

Most data in cold-atom experiments comes from images, the analysis of which is limited by our preconceptions of the patterns that could be present in the data. We focus on the well-defined case of detecting dark solitons—appearing as local density …

Machine-learning enhanced dark soliton detection in Bose–Einstein condensates Read more »

In cold atom experiments, each image of light refracted and absorbed by an atomic ensemble carries a remarkable amount of information. Numerous imaging techniques including absorption, fluorescence, and phase-contrast are commonly used. Other techniques such as off-resonance defocused imaging (ORDI, …

Multiple-camera defocus imaging of ultracold atomic gases Read more »

We quantum simulated the 2D Harper-Hofstadter (HH) lattice model in a highly elongated tube geometry—three sites in circumference—using an atomic Bose-Einstein condensate. In addition to the usual transverse (out-of-plane) magnetic flux, piercing the surface of the tube, we threaded a …

Coherence and decoherence in the Harper-Hofstadter model Read more »

Spielman group alumna Dr. Dina Genkina has composed a high level write-up of Dr. Ana Valdés-Curiel’s Rashba paper! https://jqi.umd.edu/news/researchers-comb-atoms-into-novel-swirl Topological features without a lattice in Rashba spin-orbit coupled atoms; A. Valdés-Curiel, D. Trypogeorgos, Q.-Y. Liang, R. P. Anderson, and I. …

JQI writeup of: Topological features without a lattice in Rashba spin-orbit coupled atoms Read more »

Quantum simulators are a promising technology on the spectrum of quantum devices from specialized quantum experiments to universal quantum computers. These quantum devices utilize entanglement and many-particle behavior to explore and solve hard scientific, engineering, and computational problems. Rapid development …

Quantum Simulators: Architectures and Opportunities Read more »

Topological order can be found in a wide range of physical systems, from crystalline solids, photonic meta-materials and even atmospheric waves to optomechanic, acoustic and atomic systems. Topological systems are a robust foundation for creating quantized channels for transporting electrical …

Topological features without a lattice in Rashba spin-orbit coupled atoms Read more »

Weak measurement in tandem with real-time feedback control is a new route toward engineering novel nonequilibrium quantum matter. Here we develop a theoretical toolbox for quantum feedback control of multicomponent Bose-Einstein condensates (BECs) using backaction-limited weak measurements in conjunction with …

Feedback induced magnetic phases in binary Bose-Einstein condensates Read more »