Nonlinear optical single crystal of l-Cystine hydrochloride: Insights into the crystalline perfection, thermal, mechanical and optical properties for device fabrication

Now days, nonlinear optical materials are subjected to extensive research owing to their versatility towards various photonic applications. In the present article, twin free l-Cystine hydrochloride single crystals were grown using conventional slow evaporation solution technique. The powder X-ray diffraction pattern confirmed that the titled compound belongs to monoclinic crystal system having space group C2. Using FWHM of each diffracting peak, the strain present within the lattice was calculated. Through High Resolution XRD, the crystal quality was scrutinized and found that the grown single crystal is free from any type of defects and grain boundaries. For examination of optical homogeneity of the crystal, birefringence studies were conducted which revealed that there is only one fringe in the interferogram suggesting a good optical homogeneity. Further, various thermal transport parameters were calculated using Photopyroelectric technique. Apart from that, its mechanical strength was assessed at nanoscale through Nano indentation technique. Piezoelectric and ferroelectric studies were also carried out on the titled compound.