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Coherent transfer of an optical carrier over 251 km



Nathan R. Newbury, Paul A. Williams, William C. Swann


We transfer of an optical frequency over 251 km of optical fiber with a residual instability of 6×10-19 at 100 s. This instability and the associated timing jitter are limited fundamentally by the noise on the optical fiber and link length. We give a simple expression for calculating the achievable instability and jitter over a fiber link. Transfer of optical stability over this long distance requires a highly coherent optical source, provided here by a cw fiber laser locked to a high finesse optical cavity. A sufficient optical carrier signal is delivered to the remote fiber end by incorporating two-way, in-line erbium doped fiber amplifiers to balance the 62 dB link loss.
Optics Letters


coherent communications, frequency transfer


Newbury, N. , Williams, P. and Swann, W. (2007), Coherent transfer of an optical carrier over 251 km, Optics Letters, [online], (Accessed April 24, 2024)
Created October 15, 2007, Updated February 17, 2017