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arXiv · 1807.00117

High Power, Tunable, Continuous-Wave Fiber Lasers in the L-band using Cascaded Raman Amplifiers

S Arun·Vishal Choudhury·Roopa Prakash·V R Supradeepa
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Abstract

We demonstrate a high power, all-fiber, tunable laser source that can operate in the L-band region. A low power, tunable input laser is amplified with a recently proposed, high efficiency, 6th order cascaded Raman amplifier. The proposed system is scalable and overcomes the limitations of Erbium and Erbium-Ytterbium co-doped fiber lasers for power scaling. A tunable Erbium-Ytterbium co-doped fiber ring laser generating ~0.5W of power and tunable in the 1560-1590 nm wavelength range is utilized as the seed source. The output from the seed laser is amplified to ~24 W using 6th order cascaded Raman amplification. A high power Yb laser operating at 1117nm is used as the pump laser for driving the Raman conversions. The operating wavelength of the demonstrated laser in the eye-safe, atmospherically transparent region enables high power free-space applications. In addition, this source enables other interesting applications such as high power supercontinuum generation with conventional silica fibers.

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S Arun, Vishal Choudhury, Roopa Prakash, V R Supradeepa. 2018-06-30. High Power, Tunable, Continuous-Wave Fiber Lasers in the L-band using Cascaded Raman Amplifiers. https://doi.org/10.1109/lpt.2018.2850850

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