Passively Q-switched and mode-locked Tm-Ho co-doped fiber laser using a WS2 saturable absorber fabricated by chemical vapor deposition

• Published in: Optics and laser technology Vol. 111; pp. 571 - 574
• Main Authors: Yang, Yingying, Yang, Song, Li, Chun, Lin, Xuechun
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-04-2019
• Subjects: Mode-locked lasers; Optical fiber lasers; Ultrafast optics; Optical fiber lasers; Ultrafast optics; Mode-locked lasers
• ISSN: 0030-3992; 1879-2545
• DOI: 10.1016/j.optlastec.2018.10.023

•Q-switched and mode-locked Tm-Ho laser with monolayer WS2 SA by CVD method.•Mode-locked pulse-duration is up to 1.07 ns.•Q-switched pulse-duration is up to 6.2 μs.
We demonstrate a passively Q-switched and mode-locked Tm-Ho co-doped fiber laser based on a WS2 saturable absorber (SA) fabricated by chemical vapor deposition method. When the pump power increases from 0.32 W to 0.38 W, the repetition rate of the Q-switched laser pulse increases 47.1 kHz to 90.1 kHz and the pulse width decreases from 6.2 μs to 1.7 μs. In addition, the mode-locking operation can also be observed by adjusting the polarization controller (PC) and mode-locked laser pulses at 1883.2 nm can be achieved at a high pump power between 0.5 W and 0.64 W. The pulse duration is 1.07 ns and repetition rate is 23.8 MHz and the pulse is the longest mode-locked pulse with WS2-SA ever reported.