Frequency detuning properties of EDFL pulses generated by harmonic mode-locking and regenerative amplification: a comparison

Abstract

We compare the frequency detuning properties of optical pulses generated from erbium-doped fiber lasers (EDFL's) by using harmonic mode-locking and regenerative amplification techniques. The frequency detuning range of regeneratively amplified pulse (17.78 kHz) is wider than that of harmonic mode-locked pulses (7 kHz). The regeneratively amplidied EDFL pulse has a smaller pulsewidth (22 ps), a higher peak power (40.7 mW), a lower phase noise (-107 dBc/Hz at offset frequency of 100 kHz), and a lower timing jitter (0.33 ps). This is attributed to that the characteristic of the gain-switched optical pulse is remained under regenerative amplification operation. Our harmonic mode-locked erbium-doped fiber laser has a lower phase noise (-100 dBc/Hz @ offset I kHz; -105 dBc/Hz @ 10 kHz) than that ever reported in a regeneratively harmonic mode-locked fiber ring laser.