Wavelength-tunable high-power picosecond pulses from a fiber-pumped diode-seeded high-gain parametric amplifier

We describe a high-gain optical parametric amplifier (OPA) and optical parametric generator (OPG) system pumped by a fiber chirped-pulse amplification source based on novel large-mode-area fiber components. 45-nJ OPG thresholds and 34% pump–signal conversion efficiencies are obtained for $\sim 4‐\mathrm{ps}$ pulses. OPA gains in excess of 75 dB and pump–signal conversion efficiencies of $\sim 39\%$ (external) are demonstrated. Furthermore, we show that injection seeding of such high-gain parametric devices by use of a low-power continuous-wave beam results in high-power $\left(>18‐\mathrm{kW}\right)$ picosecond pulses with a time–bandwidth produce of $\sim 0.65$, some ten times less than from a free-running OPG. Using such an approach, we obtain 2.7-ps 50-nJ pulses at $1.310 \mathit{\mu }\mathrm{m}$.