We demonstrate a tunable actively mode-locked fiber laser at 2 μm band. A segment of 4 m Tm-Ho-co-doped fiber is used as gain medium. Active mode locking pulse is realized by using intensity modulation and the signal source is high frequency sinusoidal signal. A tunable narrow bandwidth optical filter is used to narrow laser linewidth, suppress noise and achieve wavelength tuning. Stable actively mode-locked pulses with up to 2.2 GHz repetition rate is obtained, corresponding to 649 order harmonic mode-locked pulse train. The pulse width is about 200 ps. The signal-to-noise ratio of RF spectrum is 68 dB. The optical tuning range is 1907 nm~1927 nm.
Tunable high repetition rate actively mode-locked fiber laser at 2 μm
First published at:Oct 12, 2018
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National Natural Science Foundation of China (91338116)
Get Citation: Ma Wanzhuo, Wang Tianshu, Wang Furen, et al. Tunable high repetition rate actively mode-locked fiber laser at 2 μm[J]. Opto-Electronic Engineering, 2018, 45(10): 170662.
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