Potentials of LiGa(S1−xSex)2 mixed crystals for optical frequency conversion

Phase-matching conditions are considered for second harmonic generation (SHG) and optical parametric generation in LiGa(S1−xSex)2 mixed crystals as a function of chemical composition under the supposition of linear dependence of refractive indices on x. It has been shown that by tuning x over the range 0–1 the SHG can be realized in XY   plane for λ=2.1–7.8μm pumping at ϕ=43–90°ϕ=43–90°, in YZ   plane for λ=2.1–2.2λ=2.1–2.2 and 4.8–7.8 μm pumping at θ=0–90°θ=0–90°, and in XZ   plane for λ=1.6–11.7μm pumping at θ=0–57°θ=0–57°. The LiGa(S1−xSex)2 solid solutions are also attractive for design of tunable femtosecond pulse frequency converters with saving of pump pulse duration.