Ultra-stable optical links for space and ground applications

We have demonstrated the feasibility of a free-space ultra-stable optical link on a 3 meters test bench, operating at 100 MHz. With this type of link, it is possible to transfer a 100 MHz signal with a relative frequency stability of a few 10 −14 at one second integration time, 10 −16 at one day and a phase stability of a few picoseconds per day in presence of moderate mechanical vibrations and thermal fluctuations. The comparisons of modern clocks of distant ( −14 at one second integration time, 10 −16 at one day.