Title :
Chirped Laser Seeding for SBS Suppression in a 100-W Pulsed Erbium Fiber Amplifier
Author :
White, Jeffrey O. ; Engin, Doruk ; Akbulut, Mehmetcan ; Rakuljic, George ; Satyan, Naresh ; Vasilyev, Arseny ; Yariv, Amnon
Author_Institution :
U.S. Army Res. Lab., Adelphi, MD, USA
fDate :
6/1/2015 12:00:00 AM
Abstract :
A pulsed Er/Yb fiber amplifier is seeded with a frequency-chirped diode laser for the purpose of suppressing stimulated Brillouin scattering (SBS), as an alternative to the conventional broadband seed. SBS in the final stage of the amplifier limits the output power. A chirp of 5 ·1015 Hz/s is seen to increase the SBS threshold by nine times, compared with the case with no chirp. The final stage of the amplifier is modeled with a system of equations that are solved for the laser field, Stokes field, acoustic field, pump power, amplified spontaneous emission power, Yb inversion, and Er inversion, as a function of z and t. The experimental and theoretical results are in good agreement. The SBS threshold scales linearly with chirp, when the effective seed linewidth (the product of chirp and fiber transit time) is much greater than the Brillouin linewidth.
Keywords :
chirp modulation; erbium; optical fibre amplifiers; optical pumping; semiconductor lasers; stimulated Brillouin scattering; superradiance; ytterbium; SBS suppression; Stokes field; acoustic field; amplified spontaneous emission power; chirped laser seeding; frequency-chirped diode laser; laser field; power 100 W; pulsed Er-Yb fiber ampliher; pulsed erbium fiber amplifier; pump power; seed linewidth; stimulated Brillouin scattering; Chirp; Erbium; Erbium-doped fiber lasers; Mathematical model; Optical fiber amplifiers; Scattering; Fiber amplifiers; chirp modulation; erbium-doped fiber amplifiers; fiber amplifiers; fiber nonlinear optics; finite difference methods; numerical simulation; stimulated Brillouin scattering;
Journal_Title :
Quantum Electronics, IEEE Journal of
DOI :
10.1109/JQE.2015.2425963
