Optical nonlinearity of ZnS–polyvinyl pyrrolidone nanocomposite suspension

ZnS–polyvinyl pyrrolidone nanocomposite was prepared by a simple wet-chemical route. TEM and x-ray diffraction confirmed the formation of nanometre size ZnS particles within the polymer matrix. The average particle size was between 10 and 12 nm. The third-order susceptibility χ (3) of the nanocomposite suspension was measured by employing a single beam z -scan setup with 38 ps laser pulses at 532 nm. The results show that the ZnS nanoparticle exhibits saturable absorption and large third-order susceptibility χ (3) (10 −9 esu). The difference in optical nonlinearity between the ZnS/PVP suspension and another ZnS nanocomposite was discussed.