Measurement noise floor for a long-distance optical carrier transmission via fiber
We investigated the measurement floor and link stability for the transfer of an ultra-stable optical frequency via an optical fiber link. We achieved a near-delay-limited instability of 3x10^(-15)/(tau x Hz) for 147 km deployed fiber, and 10^(-20) (integrations time tau = 4000 s) for the noise floor.
physics.optics↗