Quantum Systems in Microgravity
Aims of the projects
Microgravity is expected to be a decisive condition for the next leap in tests of fundamental physics of gravity, relativity, and theories beyond the standard model. Promising techniques for fundamental tests in the quantum domain are matter wave sensors based on cold atoms or atom lasers, which use atoms as unperturbed microscopic test bodies for measuring inertial forces or as frequency references.
Microgravity is of high relevance for matter-wave interferometers and experiments with quantum matter, like Bose-Einstein condensates or degenerate Fermi gases, as it permits the extension of the unperturbed free fall of these test particles (wave packets) in a low-noise environment.
The Droptower in Bremen (ZARM) was chosen as the microgravity environment, since it provides both good accessibility and a better quality of microgravity than other platforms.
In 2004 the QUANTUS project (QUANTen Gase Unter Schwerelosigkeit) was launched with funding by the DLR (Deutsches Zentrum für Luft- und Raumfahrt). QUANTUS started as a feasibility study of a compact, robust and mobile experiment for the creation of a BEC in a weightlessness environment.
Due to the success of the first QUANTUS experiment, additional projects have been initiated to further investigate the potency of ultra-cold atoms in microgravity. QUANTUS-II expedites the miniaturisation of the experimental setup and will test new concepts of atom optics in microgravity. Beside the generation of a rubidium BEC, QUANTUS-II will be able to generate ultra-cold clouds of potassium and will in the future contribute to the test of the equivalence principle in the quantum domain by differential atom interferometric measurements.
The future prospect is to additionally use a sounding rocket microgravity platform. This will provide an atmospheric parabola flight, enabling durations of up to 6 minutes in microgravity. The project MAIUS will prepare the ground for ultra cold atoms beyond the mesosphere.
For these projects, innovative new laser systems and electronics need to be developed. LASUS (Lasersysteme unter Schwerelosigkeit) is a project to drive the miniaturisation of these components to its limits, demonstrating their feasibility for experiments in microgravity.
To further increase the resolution of atom interferometers in microgravity the project PRIMUS (Präzisionsinterferometrie unter Schwerelosigkeit) was also added to support the QUANTUS experiments.