STE-QUEST atom interferometer (AI) payload overview

Abstract

The STE-QUEST Weak Equivalence Principle test is based on a differential measurement between two atom interferometers, operating with Rb85 and Rb87, respectively, where the accelerations of the two atom clouds under the influence of the Earth’s gravity field are compared simultaneously. As both atom interferometers are operated at the same time, also using the same optical components, a high common-mode rejection is achieved. The instrument design is based on the expertise of the consortium, which includes the DLR-funded cold atom experiments QUANTUS (QUANTengase Unter Schwerelosigkeit) and MAIUS (Materiewelleninterferometrie Unter Schwerelosigkeit), both operated in drop-tower experiments, and the CNES-funded experiment I.C.E. (Interférométrie Cohérente pour l‘Espace) operated in zero-g parabola flights. For STEQUEST, Bose-Einstein- Condensates (BECs) are prepared in a hybrid trap (atom chip + optical dipole trap), which is beneficial with respect to power, mass and dimensions.