Optical nonlinearity of dye-doped polymer film using Z-scan technique

It is well known that some of organic materials/dyes exhibit exceptional nonlinear optical properties. In addition to it, they have several advantages compared to inorganic nonlinear materials due to easy to prepare solution or solid form and low dielectric constant which eliminates the need for poling while maintaining the refractive index. However, these organic materials have few of the drawbacks inherent in the processing of comparable inorganic materials like of intense light induced degradation or bleaching and aggregation at higher dye concentration. In order to overcome these drawbacks and for effective use of highly nonlinear dyes, we can dope the dye molecules in a polymer matrix. This idea of dye-doped polymer material matrix may increase the concentration of absorptive or fluorescence centers as well as the opto-chemical and opto-physical stability. In this paper we have studied the nonlinear optical properties of dye-doped polymer material by considering an organic dye 4-[4-(Dimethylamino)styryl]-1- docosyl pyridinium bromide, doped in a polymer matrix Polymethyl methacrylate methacrylic acid (PMMA-MA) using Z-scan technique.