Abstract

Measurement techniques relying on the Hall effect are widely used in condensed matter physics to measure the internal properties of solids, such as the charge-carrier concentrations of semiconductors and the quantum Hall effects of two-dimensional electron gases.  Taking inspiration from these techniques, we performed a Hall effect measurement on an ultracold atomic system.  Using a synthetic magnetic field to effect a Lorentz-like force a neutral Rb Bose-Einstein condensate, we studied the system’s dynamics and observed the Hall effect.  The good quantitative agreement between our measurements and a superfluid hydrodynamic model to which we compare them reveals this Hall effect’s dependence upon the irrotational superfluid properties of the BEC.  Extensions of this technique to other ultracold gas systems offer possibilities for making macroscopic measurements of internal and many-body properties.  I will also briefly discuss other recent experimental results from our laboratory, including modifying the effective range of interactions between cold atoms by dressing atoms with light and effecting a Peierls substitution for a BEC with a unique lattice potential.