110 W All Fiber Actively Q-Switched Thulium-Doped Fiber Laser

• Published in: IEEE photonics journal Vol. 7; no. 1; pp. 1 - 6
• Main Authors: Ouyang, De-qin, Zhao, Jun-qing, Zheng, Zhi-jian, Ruan, Shuang-chen, Guo, Chun-yu, Yan, Pei-guang, Xie, Wei-xin
• Format: Journal Article
• Language: English
• Published: IEEE 01.02.2015
• Subjects: actively Q-switched; fiber amplifiers; Fiber lasers; Optical fiber amplifiers; Optical fiber polarization; Power amplifiers; Power generation; Power lasers; Pump lasers; Thulium-doped fiber laser; tunable lasers; actively Q-switched; fiber amplifiers; tunable lasers; Thulium-doped fiber laser
• ISSN: 1943-0655; 1943-0647
• DOI: 10.1109/JPHOT.2015.2394308

We report a 100-W-level, repetition rate and pulsewidth tunable, all-fiber, thulium-doped master oscillator power amplifier system. The master oscillator was actively Q-switched by a fiber-coupled acousto-optic modulator. The generated pulsewidth could be tuned from 1.16 μm to 46.3 ns by adjusting modulation repetition rate from 1 kHz to 2 MHz, and the pulse repetition rate (PRR) can also be tuned from 1 kHz to 2 MHz, correspondingly. The maximum output power could be boosted to > 110 W (slope efficiency of 55%) through three-stage thulium-doped fiber (TDF) amplifiers at PRR from 100 kHz to 2 MHz. The spectrum bandwidth was about 0.8 nm at the maximum output power without obvious indication of nonlinear effects. To the best of our knowledge, this is the first demonstration of > 110-W, all-fiber, actively Q-switched TDF laser, and it has realized the largest tuning ranges both with the pulsewidth and the PRR.