SBS-managed high-peak-power nanosecond-pulse fiber-based master oscillator power amplifier

Abstract

We report on a compactly packaged Yb-doped fiber-based laser architecture featuring an actively pulse controlled, single-longitudinal-mode seeder and multistage amplifier chain terminated by a “folded” rod-type photonic crystal fiber. In this laser source, stimulated Brillouin scattering (SBS) is the power-limiting factor, but is managed by phase modulating the seeder with a pseudo-random noise signal. Pulse energy/peak power of ∼2  mJ/1.5  MW at 10 kHz repetition rate are thus obtained within ∼1.55  ns pulses of peak spectral brightness >20  kW cm−2 sr−1 Hz−1.