The linear and nonlinear optical properties of the organic nonlinear material 4‐nitro‐4’‐methylbenzylidene aniline

摘要: The organic crystal 4‐nitro‐4’‐methylbenzylidene aniline (NMBA) was identified as a promising nonlinear material by the powder technique. gave second harmonic intensity 16 times that of urea. Large single crystals dimensions 5×3×1 cm3 were grown temperature lowering seeded supersaturated ethyl acetate solution. principal dielectric axes defined orthoscopic examination. dispersions refractive indices determined to an accuracy ±0.0015 using minimum deviation technique and Maker fringe spacings. These dispersion curves fitted Sellmeier equation which allowed be ±0.0006. d coefficients d11, d33, d31, d13 evaluated at 1000, 1064, 1300 nm coefficient d11 over 200 larger than potassium dihydrogen phosphate (KDP) d36. In addition, nondiagonal d31 similar phase‐matching in 3‐acetamido‐4‐dimethylamino‐nitrobenzene (DAN). Critically phase‐matched signals observed all fundamental wavelengths. There excellent agreement between experimentally theoretical incidence angles. Noncritical conditions have been calculated are reported. Both angle wavelength noncritical phase matching is possible with this crystal.