The phase-noise characteristics of a harmonically mode-locked fiber laser are investigated with a new measurement technique called phase-encoded optical sampling. A polarization-maintaining ring laser is mode locked by use of the short-pulse electrical output of a resonant-tunneling diode oscillator, enabling it to produce 30-ps pulses at a 208-MHz repetition rate. The interferometric phase-encoded sampling technique provides 60-dB suppression of amplitude-jitter noise and allows supermode phase noise to be observed and quantified. The white-noise pulse-to-pulse timing jitter and the rms supermode timing jitter of the laser are measured to be less than 50 and 70 fs, respectively.
© 2001 Optical Society of America
Paul W. Juodawlkis, Jonathan C. Twichell, Jeffrey L. Wasserman, Gary E. Betts, and Richard C. Williamson, "Measurement of mode-locked laser timing jitter by use of phase-encoded optical sampling," Opt. Lett. 26, 289-291 (2001)