Investigation of pure, EDTA and DTPA-doped DAST single crystal for optoelectronic applications

The growth of optically good quality bulk size single crystal of pure and additives added 4-N, N-dimethylamino-4-N-methyl stilbazolium tosylate (DAST) crystal is reported by adopting the conventional slow evaporation solution technique. The grown single crystals were identified by single crystal and power X-ray Diffraction analysis. The luminescence study revealed the transition mechanism of ions. By estimating the hardness, Mayer index, yield strength, elastic stiffness constant, fracture toughness, and brittle index for the grown DAST single crystal using the Vickers micro-hardness analyzer, it is revealed that the grown crystal is a soft material. Using a continuous wave Nd-YAG laser and the standard Z-scan technique, the third-order nonlinearity of the pure and doped DAST single crystal was carefully examined. The third-order nonlinear optical properties show significantly higher values of the nonlinear absorption coefficient (β) and third-order nonlinear susceptibility (χ³). The calculated χ³ of grown pure, EDTA, and DTPA doped DAST crystals are 9.41 × 10⁻⁶, 8.06 × 10⁻⁶ and 7.92 × 10⁻⁶, respectively. The enhanced third-order nonlinear behavior suggests that the title compound is suitable for nonlinear optical applications.