We directly measured the normalized s-wave scattering cross-section of ultracold 40K atoms across a magnetic-field Feshbach resonance by colliding pairs of degenerate Fermi gases (DFGs) and imaging the scattered atoms. We extracted the scattered fraction for a range of bias …
We demonstrate that dynamical probes provide direct means of detecting the topological phase transition (TPT) between conventional and topological phases, which would otherwise be difficult to access because of loss or heating processes. We propose to avoid such heating by …
Dynamical Detection of Topological Phase Transitions in Short-Lived Atomic Systems Read more »
Bringing ultracold atomic gases into the quantum Hall regime is challenging. We engineered an effective magnetic field in a two-dimensional lattice with an elongated-strip geometry, consisting of the sites of an optical lattice in the long direction and of three …
We consider ultracold atoms in a two-dimensional optical lattice of the dice geometry in a tight-binding regime. The atoms experience a laser-assisted tunneling between the nearest neighbor sites of the dice lattice accompanied by the momentum recoil. This allows one …
Abby defended her thesis titled “An apparatus for light-less artificial gauge fields and new imaging techniques” today. Way to go!
The order parameter of a quantum-coherent many-body system can include a phase degree of freedom, which, in the presence of an electromagnetic field, depends on the choice of gauge. Because of the relationship between the phase gradient and the velocity, …
Gauge matters: observing the vortex-nucleation transition in a Bose condensate Read more »
Dan defended this thesis titled “Engineered potentials in ultracold Bose-Einstein condensates” today. Way to go!
Spin-orbit coupling is an essential ingredient in topological materials, conventional and quantum-gas-based alike. Engineered spin-orbit coupling in ultracold-atom systems—unique in their experimental control and measurement opportunities—provides a major opportunity to investigate and understand topological phenomena. Here we experimentally demonstrate and …
Tunable Spin-Orbit Coupling via Strong Driving in Ultracold-Atom Systems Read more »
We theoretically explore atomic Bose–Einstein condensates (BECs) subject to position-dependent spin–orbit coupling (SOC). This SOC can be produced by cyclically laser coupling four internal atomic ground (or metastable) states in an environment where the detuning from resonance depends on position. …
Position-dependent spin–orbit coupling for ultracold atoms Read more »
