Energy and spectral characteristics of a parametric generator based on a nonlinear ZnGeP2 crystal pumped by a Ho: YAG laser

摘要

We have experimentally realised the average generation power of a parametric generator based on a ZnGeP2 single crystal, which constituted similar to 1.5 W at an efficiency of similar to 28.6 % in the wavelength range of 3.5-4.8 mm with an average pump radiation power of similar to 5.5 W and its energy density of similar to 0.47 J cm(-2). It is shown that there are threshold conditions for the average pump power, providing the realisation of parametric generation. In this case, an increase in the generation efficiency with an increase in the energy density of pump radiation to similar to 0.4 J cm(-2) is observed; with its further increase, the output power increases due to a decrease in the parametric generation threshold. Parametric generators (PGs) based on ZnGeP2 single crystals with such characteristics are promising for solving many applied problems, including generation of tera-hertz radiation when nonlinear crystals are pumped by radiation from these PGs at difference frequency.