Sound creates light: Researchers transfer ultra-stable frequency across 480-km optical fiber link

ScienceDaily (2010-07-17) -- Researchers in Germany have found an elegant solution to transmit an optical frequency with extreme precision: they employ fiber Brillouin amplification. The new method simplifies the comparison of newly developed optical clocks and it is likely to have applications in other areas where precise synchronization is needed, for example in radio astronomy. Experts in geodesy have already approached the researchers with suggestions for joint projects.