FOKUS II - Space flight of a compact and vacuum compatible dualfrequency comb system

Frequency combs downconvert absolute optical frequency references and thereby can significantly advance time and frequency precision in satellite-based navigation systems, fundamental science, earth observation, and many other spaceborne applications. We have developed a compact and vacuum compatible double comb system, thereby minimizing volume, mass, and power consumption compared to its precursor. Apart from redundancy aspects, the two combs enable autonomous mode number determination. Here, we report on the space comb system design and experimental results of a zero-gravity parabolic space flight in connection with an iodine-referenced cw laser system.