Space-Qualified Ridge Waveguide Optical Amplifiers for Ultra-Cold Atom Experiments on the ISS

The realization of Bose-Einstein Condensates (BECs) is of great interest for both fundamental research and emerging applications such as high-precision quantum sensors, atom interferometers, gravimeters, and “atom lasers” exploiting the coherence of atomic waves [1]. To investigate fundamental principles - e.g. the equivalence of heavy mass and inertial mass - BECs have been created and examined in weightlessness in the Bremen drop tower in 2007 (QUANTUS) and on board a sounding rocket in 2017 (MAIUS) [2]. Building on these missions, further atom-optical experiments are planned for the International Space Station (ISS). All these experiments rely on coherent, monochromatic, frequency-stabilized laser light for cooling and manipulating cold atoms.