Investigation on the linear and nonlinear optical properties of a metal organic complex—Bis thiourea zinc acetate single crystal

• Single crystal of BTZA of dimension 4×0.9×0.7 cm3 was successfully grown.
• The non-linear refractive index was found to be −2.11×10−8 cm2/W.
• The nonlinear absorption coefficient was found to be −1.201×10−3 cm/W.
• The negative nonlinear refractive index shows the self defocusing nature of BTZA.
• The SHG efficiency found to 1.5 times that of KDP.

The third order nonlinear optical properties of bis thiourea zinc acetate single crystal were measured using He–Ne laser (λ=632.8 nm) by employing the Z-scan technique. The magnitude of nonlinear refractive index and nonlinear absorption coefficient were found to be −2.11×10−8 cm2/W and −1.201×10−3 cm/W respectively. The linear refractive index of the complex was measured by the Brewster angle method and was found to be 1.483. The third order non-linear optical susceptibility χ(3) was found to be in the order of 10−6 esu. The negative non-linear absorption coefficient shows the defocusing nature of the complex which is an essential property required for the application in optical limiting application. The second harmonic generation efficiency of the complex was studied using the Powder Kurtz method and was found to be 1.5 times greater than that of KDP.