Studies on linear and nonlinear optical properties of 4-N,N-dimethylamino-4′-N′-methyl-stilbazolium 2,4,6-trimethylbenzenesulfonate crystal

Abstract

4-N,N-dimethylamino-4′-N′-methyl-stilbazolium 2,4,6-trimethylbenzenesulfonate (DSTMS) terahertz organic material has been synthesized by the knoevenagel condensation method. DSTMS single crystals were grown in methanol by slow-cooling method. The linear optical property of DSTMS crystal has been studied using UV–Vis-NIR spectroscopy in the wavelength range 190–1100 nm and optical constants are calculated theoretically. The magnitude of nonlinear refractive index (10−10 m2/W), nonlinear absorption (10−3 m/W) and third order nonlinear susceptibility (10−4 esu) has been studied using Z-scan technique. Dielectric property of DSTMS crystal has been studied at frequency range 50 Hz–5 MHz. The electronic properties such as valence electron plasma energy, penn gap, fermi energy, electronic polarization, electric susceptibility of the grown crystal has been studied. Photoluminescence spectrum was recorded using xenon lamp in the range of 450–700 nm. Laser optical damage threshold of DSTMS crystal was calculated (3.57 GW/cm2) using pulsed Nd-YAG laser (1064 nm) of repetition rate 10 ns. The refractive index of the crystal (1.571) has been measured using Abbe’s Refractometer. The optical limiting behaviour of DSTMS crystal has been studied using Nd-YAG laser. The response time (τ) of optical limiting power for the crystals is 10−11 s.