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 amp lification source based on novel large-mode-area fiber components. 45- nJ OPG thresholds and 34% pump-signal conversion efficiencies are obta ined for similar to 4-ps pulses. OPA gains in excess of 75 dB and pump -signal conversion efficiencies of similar to 39% (external) are demon strated. 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 (>18-kW) picosecond pulses with a time-bandwidth produc e of similar to 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 mu m. (C) 1998 Optical Society of America.