Twin Matter Waves for Interferometry Beyond the Classical Limit

See allHide authors and affiliations

Science  13 Oct 2011:
DOI: 10.1126/science.1208798


Interferometers with atomic ensembles constitute an integral part of modern precision metrology. However, these interferometers are fundamentally restricted by the shot noise limit, which can only be overcome by creating quantum entanglement among the atoms. We used spin dynamics in Bose-Einstein condensates to create large ensembles of up to 104 pair-correlated atoms with an interferometric sensitivity 1.611.1+0.98 dB beyond the shot noise limit. Our proof-of-principle results point the way toward a new generation of atom interferometers.