We present theoretical predictions and experimental measurements for the achievable phase noise, timing jitter, and frequency stability in the coherent transport of an optical frequency over a fiber-optic link. Both technical and fundamental limitations to the coherent transfer are discussed. Measurements on the coherent transfer of an optical carrier over links ranging from 38 km to 251 km demonstrate good agreement with theory. With appropriate experimental design and bidirectional transfer on a single optical fiber, the frequency instability can reach the fundamental limit imposed by delay-unsuppressed phase noise from the fiber link, yielding a frequency instability which scales as link length to the 3/2 power. For two-way transfer on separate outgoing and return fibers, the instability is severely limited by differential fiber noise.
Citation: Journal of the Optical Society of America B-Optical Physics
Issue: No. 8
Pub Type: Journals
Optical frequency transfer, doppler stabilization, phase stabilization