Papers Published – Page 2 – Quantum matter from atomic gases

Dynamical instability of 3d stationary and traveling planar dark solitons

By Ian Spielman Posted on 2022/11/21 Posted in Group News, Papers Published, RbK

Here we revisit the topic of stationary and propagating solitonic excitations in self-repulsive three-dimensional (3D) Bose–Einstein condensates by quantitatively comparing theoretical analysis and associated numerical computations with our experimental results. Motivated by numerous experimental efforts, including our own herein, we …

Dynamical instability of 3d stationary and traveling planar dark solitons Read more »

Dynamically Induced Symmetry Breaking and Out-of-Equilibrium Topology in a 1D Quantum System

By Ian Spielman Posted on 2022/09/16 Posted in Group News, Papers Published, RbK

Nontrivial topology in lattices is characterized by invariants—such as the Zak phase for one-dimensional (1D) lattices—derived from wave functions covering the Brillouin zone. We realize the 1D bipartite Rice-Mele (RM) lattice using ultracold 87Rb and focus on lattice configurations possessing …

Dynamically Induced Symmetry Breaking and Out-of-Equilibrium Topology in a 1D Quantum System Read more »

Floquet Engineering Topological Dirac Bands

By Ian Spielman Posted on 2022/07/22 Posted in Group News, Papers Published, RbK

We experimentally realized a time-periodically modulated 1D lattice for ultracold atoms featuring a pair of linear bands, each with a Floquet winding number. These bands are spin-momentum locked and almost perfectly linear everywhere in the Brillouin zone: a near-ideal realization …

Floquet Engineering Topological Dirac Bands Read more »

Combining machine learning with physics: A framework for tracking and sorting multiple dark solitons

By Ian Spielman Posted on 2022/05/31 Posted in Group News, Papers Published

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 …

Combining machine learning with physics: A framework for tracking and sorting multiple dark solitons Read more »

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

By Ian Spielman Posted on 2022/05/12 Posted in ErNa, Group News, Papers Published

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 »

Feedback-stabilized dynamical steady states in the Bose-Hubbard model

By Ian Spielman Posted on 2021/11/01 Posted in Group News, Papers Published, Theory

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 »

Wilson loop and Wilczek-Zee phase from a non-Abelian gauge field

By Ian Spielman Posted on 2021/09/30 Posted in Group News, Papers Published, RbChip, Theory

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 »

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

By Ian Spielman Posted on 2021/06/16 Posted in Group News, Papers Published, RbK, Theory

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 »

Multiple-camera defocus imaging of ultracold atomic gases

By Ian Spielman Posted on 2021/05/19 Posted in Group News, Papers Published, RbLi

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 »

Coherence and decoherence in the Harper-Hofstadter model

By Ian Spielman Posted on 2021/05/18 Posted in Group News, Papers Published, RbLi

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 »

Category: Papers Published