Crystal engineering and physicochemical properties of l-cysteine cadmium chloride (LCC) for frequency-doubling and optical limiting applications

Adapting the solution growth method, l -cysteine cadmium chloride (LCC) crystal was synthesized, and by using a single-crystal X-ray diffraction analysis, orthorhombic system was confirmed. From the powder XRD pattern, the crystalline nature of LCC crystal was revealed. With the help of FTIR spectroscopy, various functional groups present in the LCC crystal were identified. The UV–Vis-NIR spectroscopy analysis indicates a lower cutoff wavelength of 244 nm with an optical band gap of 3.77 eV. The linear optical properties such as optical conductivity (σ opt ) and electric susceptibility (χ e ) are also evaluated. By conducting the test of mechanical analysis, the hard nature of the LCC crystal was identified. A higher thermal withstand capacity of 392 °C was determined using TG/DT analysis. During the process, the high-energy-laser withstand capacity of the material was analyzed by a laser damage threshold analysis and it was found to be 6.87 GW/cm 2 . Kurtz and Perry's method was used to measure the SHG efficiency and observed to be 2.32 times higher than KDP. The negative nonlinear refractive index of the LCC crystal was confirmed by Z-scan experiment and the nonlinear refractive index ( n 2 = 2.73 × 10 –11 m 3 /W), nonlinear absorption coefficient (β = 6.111 × 10 –5 m/W), third-order nonlinear optical susceptibility (χ 3 = 1.229 × 10 –9 esu). The optical limiting performance of the LCC crystal displays a linear variation output for varying input laser power in low intensities and the optical limiting threshold value was found to be 46.9 mW. Etching analysis confirms the dislocation growth mechanism of the grown LCC crystal.