Fiber-Amplified Pulses Beyond the Gain Narrowing Limit for Seeding an OPA

Abstract

We report on the design and numerical simulation of a tunable, near-infrared (NIR) femtosecond noncollinear optical parametric amplifier (OPA) seeded by a nonlinear fiber amplifier operating in the parabolic and gain-managed regime. With microjoule-level pump pulses in the visible, we achieved amplification bandwidths of signal and idler pulses between 1010-1170 nm and 920-1050 nm, respectively, and whose second harmonics correspond to the visible range between ~460-585 nm. The estimated quantum efficiency for the conversion of the pump to signal and idler pulses combined was greater than 15%. This appreciable value in a single OPA stage is due to the high spectral energy density of the fiber-amplified broadband pulse - about 30 times greater in the 1 {\mu}m range when compared to white-light continuum (WLC) pulses, which are often used to seed commercial OPAs. When combined with their excellent spatial beam quality and full coherence across their entire bandwidth, fiber-amplified pulses enable more efficient engineering and application of OPAs in the visible and NIR.