Optical parametric amplification using the phase matching retracing behavior in MgO:LiNbO3 for generation of intense widely tunable mid-infrared 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 range. A regeneratively amplified 2 ps Ti:sapphire laser and a tunable 3 ns narrow-band optical parametric oscillator serve as pumping and seeding sources; respectively. By setting the crystal at a phase matching angle very close to the retracing point of the crystal for a pumping wavelength 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 demonstrated 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.