1.36-kW Spectral-Narrowing Fiber Laser Seeded by Random Fiber Laser

A single-mode 1.36-kW output power fiber amplifier with 0.22-nm full-width at half-maximum (FWHM) is realized by employing a master oscillator power amplifier (MOPA) configuration, seeded by a random fiber laser (RFL). We demonstrated an approach of narrowing the emission spectrum of the fiber amplifier by lengthening the passive fiber in the seed through inverse four-wave-mix effect. This method is expected to be used for narrowing the emission spectrum of fiber amplifiers, which makes them more suitable for the applications that require narrow-linewidth high-power lasing.