Electronic properties such as current flow are generally independent of the electron’s spin angular momentum, an internal degree of freedom possessed by quantum particles. The spin Hall effect, first proposed 40 years ago, is an unusual class of phenomena in …
The Aubry-André or Harper (AAH) model has been the subject of extensive theoretical research in the context of quantum localization. Recently, it was shown that one-dimensional quasicrystals described by the incommensurate AAH model has a nontrivial topology. In this Letter, …
Topological Zero-Energy Modes in Gapless Commensurate Aubry-André-Harper Models Read more »
An integrated optical dipole trap uses two-color (red and blue-detuned) traveling evanescent wave fields for trapping cold neutral atoms. To achieve longitudinal confinement, we propose using an integrated optical waveguide coupler, which provides a potential gradient along the beam propagation …
Integrated optical dipole trap for cold neutral atoms with an optical waveguide coupler Read more »
Matthew Beeler —the first observer of a spin-Hall effect in a Bose-Einstein condensate— just moved on to a staff scientist position at the the Johns Hopkins University Applied Physics Laboratory. Or we think he has, his work is classified.
Ross got a job at National Physical Laboratory (NPL) in London! Way to go! We will sorely miss Ross, but he leaves behind fantastic work: he first engineered artificial d– and g– waves in colliding Bose-Einstein condensates; as that was …
We consider a quantum quench in which two initially independent condensates are suddenly coupled and study the subsequent “rephasing” dynamics. For weak tunneling couplings, the time evolution of physical observables is predicted to follow universal scaling laws, connecting the short-time …
Spin–orbit coupling links a particle’s velocity to its quantum-mechanical spin, and is essential in numerous condensed matter phenomena, including topological insulators and Majorana fermions. In solid-state materials, spin–orbit coupling originates from the movement of electrons in a crystal’s intrinsic electric …
We have observed well-defined phase slips between quantized persistent current states around a toroidal atomic (23Na) Bose-Einstein condensate. These phase slips are induced by a weak link (a localized region of reduced superfluid density) rotated slowly around the ring. This …
Driving Phase Slips in a Superfluid Atom Circuit with a Rotating Weak Link Read more »
Fermions, as a major class of quantum particles, provide platforms for quantum information processing beyond the possibilities of spins or bosons, which have been studied more extensively. One particularly interesting model to study, in view of recent progress in manipulating …
We present a method for accurate determination of atomic transition matrix elements at the 10-3 level. Measurements of the ac Stark (light) shift around “magic-zero” wavelengths, where the light shift vanishes, provide precise constraints on the matrix elements. We make …
Precision Measurement of Transition Matrix Elements via Light Shift Cancellation Read more »