Bose-Einstein-condensate interferometer with macroscopic arm separation

Abstract

A Michelson interferometer using Bose-Einstein condensates is demonstrated with coherence times of up to $44\phantom{\rule{0.3em}{0ex}}\mathrm{ms}$ and arm separations up to $180\phantom{\rule{0.3em}{0ex}}\mathrm{\ensuremath{\mu}}\mathrm{m}$. This arm separation is larger than that observed for any previous atom interferometer. The device uses atoms weakly confined in a magnetic guide and the atomic motion is controlled using Bragg interactions with an off-resonant standing-wave laser beam.