7 December 2020
Space Science at Droptower SEMINAR TALK
Location: ZARM Bremen - Online seminar
When: 07.12.2020, 17:00 CET - Online
Speaker: Holger Müller (University of California, Berkeley)
Title: Probing gravity by holding atoms
Abstract: Atom interferometers are powerful instruments for fundamental physics and inertial sensing. Their performance derives from a long interrogation time during which the matter waves accumulate phase shifts, which has been limited to about 2.5 seconds. By suspending atomic wave packets in a lattice formed by the mode of an optical cavity, we realize an interrogation time of 20 seconds. Our approach allows gravitational potentials to be measured by holding, rather than dropping, atoms. After seconds of hold time, gravitational potential energy differences from as little as micrometers of vertical separation generate megaradians of interferometer phase. This trapped geometry suppresses the phase variance due to vibrations by three to four orders of magnitude, overcoming the dominant noise source in atom-interferometric gravimeters. We will close by an outlook of how these methods could be used to realize fully-guided interferometers on mobile platforms.