Effect of Ultraviolet (UV) Light Treatment on the Nonlinear Optical Properties of Red Lake Doped Polyvinyl Chloride (PVC) Film

摘要

The effect of ultraviolet (UV) light treatment on the nonlinear optical properties of red lake doped commercial polyvinyl chloride (PVC) film is studied employing different optical techniques. PVC films were exposed to UV radiation from 1 to 5 days. Experiments are performed using the second harmonic of a continuous Nd-YAG laser beam at 532 nm wavelength and 20 mW power. By obtaining the beam profile propagated through pristine and treated samples, nonlinear refractive index of red lake doped PVC films is found to be positive. This magnitude is increased due to UV treatment. The optical limiting behaviour of samples is investigated by measurement of transmission through the sample, which is remained unchanged in comparison with pristine sample. The third order nonlinearity of UV treated samples is measured using Z-scan method. Experimental results show that real and imaginary parts of nonlinear susceptibility increase with increasing the time of treatment.