Description
The 15m high Very Long Baseline Atom Interferometry (VLBAI) facility
in Hannover, Germany, aims for sub nm/s^2 gravity measurement sensitivities. Using light-pulse atom interferometry, the VLBAI facility enables to perform accurate measurements of inertial effects thus making it a useful device for metrology and tests of fundamental physics. The sensitivity of light-pulse atom interferometers depends on several factors one of which being the freefall time. A second-long free fall of the atoms allows to reach acceleration sensitivities of 1nm/s2, comparable to the best classical superconducting gravimeters. At the VLBAI facility, a freefall time of 2.8s can be reached. In addition, excellent control over the environment and a large atomic flux is necessary to reduce systematic effects and achieve shot-noise limited sensitivities.
We present the current status of the VLBAI facility and outline its
distinguishing aspects that will include sources of ultracold ytterbium
and rubidium, a 10m long UHV baseline magnetically shielded to below 1.5nT/m, and a inertial reference seismic attentuation system.
