Generation of difference-frequency radiation in mid- and far-IR ranges by using subpicosecond and picosecond semiconductor lasers

The possibility of the efficient generation of difference-frequency radiation in the mid- and far-IR spectral ranges in the case of phase matching between a nonlinear polarisation wave and a radiation mode at the difference frequency by using ~1-μm subpicosecond and picosecond semiconductor lasers is considered. For a laser with a planar waveguide of width 100 μm emitting 100-W pulses and 10 W of cw power the near-IR range, the output power at the difference frequency achieves 1 mW in the wavelength region from 5 to 9 μm and 0.2 mW in the wavelength region above 60 μm at room temperature.