Adaptive inelastic magnetic mirror for Bose-Einstein condensates

Abstract

We report the reflection and focusing of a Bose-Einstein condensate by a pulsed magnetic mirror. The mirror is adaptive, inelastic, and has extremely high optical quality. Deviations from specularity are below 1 mrad rms --- almost an order of magnitude better than other atomic mirrors. The mirror has been used to realize the atom-optical analog of a beam expander, producing an ultracold collimated fountain of matter waves. The results of these experiments are in good agreement with simple theoretical models.