OPTICAL PARAMETRIC AMPLIFICATION USING THE PHASE-MATCHING RETRACING BEHAVIOR IN MGO-LINBO3 FOR GENERATION OF INTENSE WIDELY TUNABLE MIDINFRARED PULSES

We report on a new scheme for seeded optical parametric amplification using the phase matching retracing behavior in a 7% MgO:LiNbO3 crystal to generate picosecond widely tunable pulses in the mid-infrared rang e. A regeneratively amplified 2 ps Ti:sapphire laser and a tunable 3 n s narrow-band optical parametric oscillator serve as pumping and seedi ng sources; respectively. By setting the crystal at a phase matching a ngle very close to the retracing point of the crystal for a pumping wa velength of 778 nm, a wide tunability from 3.35 to 3.85 mu m of 2.3 ps pulses at a very intense constant pulse energy of 60 mu J has been de monstrated by varying only the seeding wavelength from the nanosecond optical parametric oscillator. The constant energy range could be blue - or redshifted as a function of the pumping wavelength.