DESIRE - Dark energy search using atom interferometry in the Einstein Elevator*

Light pulse atom interferometry is a promising tool to search for new microscopic forces on the dynamics of neutral atoms. The accuracy of such measurements scales with the square of the time between the atom interferometer laser pulses. On typical groundbased devices, it is therefore limited by the amount of available freefall time which is usually constrained by the size of the apparatus. One possibility to overcome this limitation is to use Bose-Einstein condensates (BECs) with ultralow expansion rates in microgravity.

The experiment DESIRE will utilize the newly commissioned active drop tower facility Einstein Elevator, which offers up to 4s of microgravity (residual acceleration < 1E-6m/s^2) in catapult mode and up to 300 drops per day. The apparatus is a derivative of the sounding-rocket experiment MAIUS-1 [1] and therefore already optimized for autonomous operation. It demonstrated rapid production of BECs of Rb-87 with ultralow expansion rates and was upgraded to offer capabilities for multiorder Bragg interferometry at the timescale of a second.

The vacuum chamber is connected to a testmass with a periodically modulated shape which specifically has been designed to search for Chameleon field dark energy [2]. The periodic shape of the testmass will be probed by a multiloop atom interferometer which allows to disentangle Chameleon fields from gravitational effects with different periodicity. In differential mode, systematic effects like residual vibrations of the capsule will be suppressed.

This poster shows the experimental setup, its current status and describes its capabilities to search for new physics.

[1] D. Becker, M. D. Lachmann, S. T. Seidel, et al.: Nature 562, 391–395 (2018)

[2] S.-W. Chiow, Nan Yu. Phys. Rev. D 97, 044043 (2018)