Far-field diffraction patterns and optical limiting properties of bisdemethoxycurcumin solution under CW laser illumination

In this work, nonlinear optical properties of bisdemethoxycurcumin solution were studied using diffraction ring patterns method. Multiple diffraction rings observed as a continuous wave (CW) laser beam passes through a bisdemethoxycurcumin solution. The nonlinear refractive index, n2, and change in refractive index, Δn, for sample were determined from the number of observed rings, and are found to be 0.8327 × 10−6 cm2/W and 0.00946 respectively. The evolution of the diffraction ring patterns are numerically studied using the Fresnel-Kirchhoff diffraction integral theory. The experimental findings are in good agreement with theoretical analysis. Also the optical limiting properties of the sample were measured at 473 nm. The obtained results proved that the sample bear good optical limiting property.