Optical Materials Express · 2017 · 47 citations · 31 references
Natural SciencesMaterials SciencePhysicsCrystal StructureOptical MaterialsOpticsElectro-optic EffectsNonlinear Optical MaterialsNonlinear OpticsOptical Properties Of MaterialsOptical Properties Of SolidsRefractive IndexFrequency ConversionNonlinear AbsorptionNonlinear Optical PropertiesNonlinear RefractionNonlinear Refractive IndexOptical AbsorptionOptical Frequency ConversionSelf-focusing
High-quality KDP and DKDP crystals with 12%, 70% and 80%-deuterium content were grown by the conventional temperature cooling method. The nonlinear optical characteristics of K(DxH1-x)2PO4 crystals, including nonlinear absorption and refraction, were systematically investigated through the Z-scan method at λ = 532 nm. The results demonstrate the existence of nonlinear absorption and refraction, and a nonlinear refractive index with a positive sign indicates the generation of self-focusing effect. Moreover, the results indicate that nonlinear absorption and refraction were associated with crystal direction and structure, especially the distribution of H2PO4 - or D2PO4 - groups. For K(DxH1-x)2PO4 crystals, a similar rule of β was z > I > II, while n2 (or χR(3)) was z > II ≈I. These results will evoke more attention to KDP and DKDP applications, especially frequency conversion and electro-optic switch.
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