Effect of xylenol orange on the crystalline perfection, optical, piezoelectric and NLO behavior of unidirectionally grown imidazolium L-Tartrate single crystal

Abstract

Pure and 0.1 mol% Xylenol orange (XO) doped Imidazolium L-tartrate (IMLT) nonlinear optical (NLO) single crystals were grown using Sankaranarayanan–Ramasamy (SR) method of uniaxial solution crystallization technique. The pure IMLT crystal is 100 mm in length and 15 mm in diameter. The doped IMLT crystal is 25 mm in length and 10 mm in diameter. UV–Vis-NIR spectrum shows that the pure and XO doped IMLT crystals' cut off wavelength is 235 nm. High-resolution X-ray diffraction (HRXRD) measurement and birefringence interferometry confirm that the SR method grown crystal has good crystalline perfection and optical homogeneity. The wavelength dependent refractive index and piezoelectric d33 coefficient were measured. The difference refractive index (Δn) of (100) plane in parallel and perpendicular directions shows a strong dependence on wavelength. The dielectric constant, hardness and SHG conversion efficiency were also increased as a result of XO dye doping in IMLT crystal.