Atom interferometry is based on the measurement of phase differences in coherent matter waves. As such, it is an ideal technique for measuring inertial forces caused by e.g. acceleration and rotation. The precision of the measurements is provided by the standing light wave imprinting its position-dependent phase onto the matter waves and therefore acting as a fine-spaced ruler.
Being based on single atoms in superposition states, atom interferometry based sensors can perform non-classical measurements and new perspectives for tests of fundamental physics. They have the ability to probe the limits of quantum physics and general relativity, though this requires highly precise and well-controlled devices.
Here we report on the commissioning of the Very Long Baseline Atom Interferometry (VLBAI) facility in the Hannover Institute of Technology. It will be composed of a 10.5 m high magnetically shielded free-fall baseline, two atomic source chambers featuring Bose-condensed rubidium and ytterbium, as well as a high-performance seismic attenuation system. This allows for a variety of tests of fundamental physics in a well-controlled environment [1-3].
Besides presenting the current status of the facility we discuss its prospects for fundamental physics measurements. These include quantum clock interferometry for gravitational redshift tests  and differential dual-species interferometers for tests of the universality of free fall , but also tests of macroscopicity and fundamental decoherence by separation of superposition states on the meter scale .
 D. Schlippert et al, arXiv:1909.08524 (2019)
 É. Wodey et al, Review of Scientific Instruments 91, 035117 (2020)
 M. Schilling et al, Journal of Geodesy 94, 122 (2020)
 F. Di Pumpo et al, PRX Quantum 2, 040333 (2021)
 J. Hartwig et al, New Journal of Physics 17, 035011 (2015)
 B. Schrinski et al, Physical Review Research 2, 033034 (2020)
|Presenter name||Dorothee Tell|
|How will you attend ICAP-27?||I am planning on in-person attendance|