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

TL;DR

This paper presents a high power, tunable, all-fiber laser operating in the L-band, achieved through cascaded Raman amplification, overcoming traditional fiber laser limitations for power scaling and enabling applications like free-space communication and supercontinuum generation.

Contribution

The work introduces a scalable, high-efficiency cascaded Raman amplifier system for L-band fiber lasers, surpassing limitations of conventional doped fiber lasers.

Findings

Achieved ~24 W output power in the 1560-1590 nm range.

Demonstrated tunability in the 1560-1590 nm wavelength range.

Enabled high power applications in the eye-safe, atmospheric transparency region.

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.