Luminescence, laser induced nonlinear optical and surface microscopic studies of potassium thiourea chloride crystal

Abstract

The present communication is aimed to explore the optical properties of organometallic nonlinear optical potassium thiourea chloride (PTC) crystal by means of UV–vis, luminescence, Z-scan, laser damage threshold and etching studies. The PTC single crystal of optimum size (11 × 12 × 04) mm3 has been grown from solution by slow evaporation technique. The qualitative analysis of PTC crystal has been confirmed by means of energy dispersive spectroscopic technique. The UV–vis study has been carried out to assess the optical transparency of PTC crystal in visible region of interest. The photoluminescence study has been accomplished to ascertain the color centered photoluminescence emission nature of PTC crystal in optical spectrum. The laser damage threshold (LDT) value of PTC crystal has been determined by pulse multi shot method using the Nd:YAG laser operating at 1064 nm and the LDT of PTC crystal is found to be in the range of MW/cm2. The microscopic studies were performed by means of etching analysis to discuss the growth habit and structural defects associated with PTC crystal surface. The third order nonlinear optical nature of PTC crystal has been investigated at 632.8 nm employing the He-Ne laser assisted Z-scan studies. The third order nonlinear optical parameters such as susceptibility (χ3), absorption coefficient (β), refractive index (n2) and figure of merit have been evaluated using the Z-scan transmittance data. The NLO device applications of PTC crystal have been discussed in light of observed results.