Category: Papers Published

Feshbach enhanced s-wave scattering of fermions: direct observation with optimized absorption imaging

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

Posted in Atomtronics, Group News, Papers Published, RbK

Dynamical Detection of Topological Phase Transitions in Short-Lived Atomic Systems

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

Posted in Group News, Papers Published, Theory

Published in Science: Visualizing edge states with an atomic Bose gas in the quantum Hall regime

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

Posted in Group News, Papers Published, RbK

Gauge matters: observing the vortex-nucleation transition in a Bose condensate

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,

Posted in Group News, Papers Published, RbK, Uncategorized

Karina and Ian’s book chapter on Mott/Superfluid physics published

Karina and Ian’s book chapter “The Mott Transition in a Bose Gas Measured Through Time of Flight” is published on page 145 of the “Annual Reviews of Cold atoms and Molecules” volume 2.  Wow, it takes a long time for

Posted in Group News, Papers Published, RbK

Measuring Topology featured as a NJP “Highlight of 2013”

Nathan Goldman et al‘s result describing techniques for measuring topology in a laser-coupled honeycomb lattice has been featured as a “Highlight of 2013” by The New Journal of Physics! This rocks! Highlights page: http://iopscience.iop.org/1367-2630/page/highlights-of-2013 Article: http://iopscience.iop.org/1367-2630/15/1/013025/article

Posted in Atomtronics, Group News, Papers Published, Theory

Quenched binary Bose-Einstein condensates: Spin-domain formation and coarsening

We explore the time evolution of two-component Bose-Einstein condensates (BECs), quasi one dimensional with respect to their spinor dynamics, following a quench from one component BECs with a U(1) order parameter into two-component condensates with a U(1)xZ2 order parameter. In

Posted in Group News, Papers Published, RbLi

Zitterbewegung featured as a NJP “Highlight of 2013”

Lindsay LeBlanc et al‘s result demonstrating Zitterbewegung in a spin-orbit coupled atomic Bose gas has been featured as a “Highlight of 2013” by The New Journal of Physics!  Way to go team! Highlights page: http://iopscience.iop.org/1367-2630/page/highlights-of-2013 Article: http://iopscience.iop.org/1367-2630/15/7/073011/article

Posted in Atomtronics, Group News, Papers Published, RbK

Optimally focused cold atom systems obtained using density-density correlations

Resonant absorption imaging is a common technique for detecting the two-dimensional column density of ultracold atom systems. In many cases, the system’s thickness along the imaging direction greatly exceeds the imaging system’s depth of field, making the identification of the

Posted in Group News, Papers Published, RbLi

Zitterbewegung: JQI writeup

S. Kelly of the JQI did a very nice writeup with awesome artwork for Lindsay’s Zitterbewegung paper as follows: In “Harry Potter and the Sorcerer’s Stone” (JK Rowling, 1997), Harry, Ron, and Hermione encounter a massive stone chessboard, one of many

Posted in Group News, Papers Published, RbK