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Low-noise fiber-laser frequency combs



Nathan R. Newbury, William C. Swann


We discuss experimental and theoretical aspects of a low-noise fiber-laser frequency comb, including the experimental configuration and the major contributions to the frequency noise and linewidth of the individual comb modes. Intra-cavity noise sources acting on the mode-locked laser determine the free-running comb linewidth and include environmental changes, pump noise, and amplified spontaneous emission (ASE). Extra-cavity noise sources acting outside of the laser typically determine the signal-to-noise ratio on the comb lines and include environmental effects, shot noise and noise generated during supercontinuum generation. Feedback strongly suppresses these intracavity noise contributions, yielding a system that operates with comb linewidths and timing jitter below the quantum limit set by the intracavity ASE. Finally, we discuss correlations in the residual noise across a phase-locked comb.
Journal of the Optical Society of America B-Optical Physics


fiber laser frequency comb, frequency metrology, mode-locked fiber laser


Newbury, N. and Swann, W. (2007), Low-noise fiber-laser frequency combs, Journal of the Optical Society of America B-Optical Physics, [online], (Accessed July 24, 2024)


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Created July 18, 2007, Updated October 12, 2021