In ultracold-atom experiments, data often comes in the form of images which suffer information loss inherent in the techniques used to prepare and measure the system. This is particularly problematic when the processes of interest are complicated, such as interactions …
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 …
On this day, April 4, 2022, Shangjie Guo defended his thesis. Congratulations Shangjie!
High-resolution imaging of ultracold atoms typically requires custom high numerical aperture (NA) optics, as is the case for quantum gas microscopy. These high NA objectives involve many optical elements, each of which contributes to loss and light scattering, making them …
Self-Bayesian aberration removal via constraints for ultracold atom microscopy Read more »
The implementation of a combination of continuous weak measurement and classical feedback provides a powerful tool for controlling the evolution of quantum systems. In this paper, we investigate the potential of this approach from three perspectives. First, we consider a …
Feedback-stabilized dynamical steady states in the Bose-Hubbard model Read more »
Quantum states can acquire a geometric phase called the Berry phase after adiabatically traversing a closed loop, which depends on the path not the rate of motion. The Berry phase is analogous to the Aharonov–Bohm phase derived from the electromagnetic …
Wilson loop and Wilczek-Zee phase from a non-Abelian gauge field Read more »
The University of Maryland has been tapped to lead a multi-institutional effort supported by the National Science Foundation (NSF) that is focused on developing quantum simulation devices that can understand, and thereby exploit, the rich behavior of complex quantum systems. The NSF Quantum …
Quantum leap challenge institute for robust quantum simulation: funded! 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 »