Laser-induced nonlinear far-field diffraction patterns of disperse azo dyes

Abstract

The nonlinear optical properties of the dispersed azo dyes (orange 3, orange 13 and orange 25) were investigated using laser field-induced spatial self-phase modulation (SSPM) with continuous wave laser of 532 nm. The research of disperse azo dyes at different concentrations and incoming laser power produced diffraction ring patterns. The results of the experiment showed a large nonlinear refractive index n₂ and a large thermo-optical coefficient dn/dT. The effect of excitation laser input and time evolution on shape diffraction pattern shape was investigated. We therefore explain the collapse effect of the diffraction circle model. The results show that the type of laser input is responsible for the variation of the number of diffraction circles. The results indicated that the dispersed azo dyes are a good candidate for use as an optical limiter.