Optical properties of non-centrosymmetric mixed crystals K2(La1-xCex)(NO3)5•2 H2O (x=0-0-1-0)

Large single crystals of optical quality of the non-centrosyrnmetric orthorhombic potassium rare earth nitrate mixed crystals K-2(La1-xCex)(NO3)5 center dot 2 H2O were grown at 38 degrees C from diluted HNO3. For crystals with x = 0.0, 0.19, 0.38 and 0.66 refractive indices and their dispersion were determined with an error less than 1 center dot 10(-4) in the wavelength range 0.404 - 1.083 mu m by the prism method. Phase matching conditions for collinear SHG frequency conversion were analysed in detail, including calculation of the effective nonlinear optical susceptibility. By an appropriate choice of the firaction x of cerium the mixed crystals K2(La1-xCex)(NO3)(5 center dot)2 H2O allow an adjustment of non-critical type I phase matching conditions to a desired wavelength of the fundamental wave within the range 1.055(4) - 1.107(6) mu m. Non-critical type 11 phase matching can be tuned in the wavelength range 0.949(2) - 0.931(2) mu m.