Parametric generation of infrared picosecond pulses in LiNbO3 crystals

Efficient parametric generation of infrared radiation in LiNbO₃ crystals was obtained when these crystals were pumped with the fundamental frequency and second harmonic of a YAG:Nd³⁺ picosecond laser (the pulse repetition frequency was up to 25 Hz). The maximum energy efficiency of conversion was 17% (the energy of the parametric signal in the 2 μ range was 9×10^–4 J) and continuous frequency tuning was obtained in the 1365–4825 and 660–2700 nm ranges (for the fundamental frequency and second harmonic, respectively). The possibility of narrowing the width of the output spectrum by the use of a twocrystal system were considered.