An ultra-stable optical frequency reference for space applications

A variety of future space missions require ultra-stable optical frequency references. Setups based on Doppler-free spectroscopy of molecular iodine offer frequency stabilities in the 10−15 domain at longer integration times and have the potential to be realized space compatible on a relatively short time scale. We present a compact optical frequency reference using modulation-transfer spectroscopy of molecular iodine near 532 nm. Using a specific assembly-integration technology, this setup takes into account space mission related criteria such as compactness, robustness, MAIVT and environmental influences. With this setup, a frequency stability of 3 · 10−15 at integration times between 100 s and 10.000 s was demonstrated in a first measurement.