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A passively mode-locked fiber laser at 1.54 υm with a fundamental repetition frequency reaching 2 GHz



John Mcferran, Ljerka Nenadovic, William C. Swann, John B. Schlager, Nathan R. Newbury


We demonstrate a fundamentally mode-locked fiber laser with a repetition frequency in excess of 2 GHz at a central wavelength of 1.535 υm. Co-doped ytterbium-erbium fiber provides the gain medium for the laser, affording high gain per unit length, while a semiconductor saturable absorber mirror (SAM) provides the pulse shaping mechanism in a standing wave cavity. Results are shown confirming cw mode-locking for 1 GHz and 2 GHz repetition frequency systems. The response of the frequency comb output to pump power variations is shown to follow a single pole response. The timing jitter of a 540 MHz repetion-rate laser has been suppressed to below 100 fs through phase-lead compensated feedback to the pump power. Alternatively, a single comb line of a 850 MHz repetition-rate laser has been phase-locked to a narrow linewidth cw laser with an in-loop phase jitter of 0.06 rad2. The laser design is compatible with low-noise oscillator applications.
Optics Express


fiber lasers, metrological instrumentation., mode-locked lasers


Mcferran, J. , Nenadovic, L. , Swann, W. , Schlager, J. and Newbury, N. (2007), A passively mode-locked fiber laser at 1.54 υm with a fundamental repetition frequency reaching 2 GHz, Optics Express, [online], (Accessed July 17, 2024)


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Created September 25, 2007, Updated October 12, 2021