Cascade picosecond optical parametric amplification for generating radiation in the 2.1 [formula omitted

Abstract

The paper demonstrates the experimental implementation of a broadband picosecond radiation source with a wavelength of 2.0−2.2μm based on a cascade parametric amplifier. To do this, in the first cascade, as a result of parametric luminescence in the MgO:PPLN fan-out crystal, pumped by Nd:YAG laser pulses (90 ps, 10 Hz), radiation with a wavelength of 2.1μm and a pulse energy of ∼185 μJ at a pump energy of 6.5 mJ was generated. To increase the output radiation energy to a level of ∼840 μJ, a second parametric amplification cascade based on two KTiOPO4 crystals with a walk-off angle compensation was used. The results of numerical simulation of the spatial and energy characteristics of the radiation being generated are in good agreement with the experimental results. The developed picosecond 2.1μm radiation source is designed to be used for mid-IR range supercontinuum generation in non-oxide crystals.