Pulsed amplified spontaneous Raman emission at 2.2 μm in silica-based fiber
All-fiber source at 2.2 μm is investigated with amplified spontaneous Raman scattering process in highly Ge-doped silica fiber. By optimizing the gain fiber length, the second-order Raman Stokes light at 2.43 μm is suppressed and 3 W first-order Raman Stokes light at 2.2 μm is obtained with a homemade 2-μm Q-switched Tm3+-doped fiber laser as pump source. The conversion efficiency is 35.9 % from 2.0 to 2.2 μm, and the peak power of the 2.2-μm laser is about 400 W.
KeywordsFiber Length Incident Pump Power Raman Gain Seed Laser Dope Fiber Laser
The work was supported by the National Natural Science Foundation of China (Nos. 61575210 and 61378026).