چكيده به لاتين
Nonlinear optical behavior of nanostructures is considered as the main mechanism of photonic components. Due to the unique nonlinear optical properties of nanostructures, effects like optical bistability, saturable absorption, optical limiting, modulation instability, etc are stronger and the required optical threshold power is extremely lower. Thus, a comprehensive research is needed to elucidate the pathway for designers and engineers of photonic devices.
In this research, firstly the nonlinear optical behavior of nonmetallic nanocolloids are investigated by focusing on saturable absorption, optical bistability and modulation instability. To achieve so, an analytical solution of Haus equation and the predictor-corrector numerical method for solving nonlinear Schrodinger equation are described and used. Nonideal gas model of nonlinearity is also used to explain the nonlinear optical trait of colloidal nanoparticles. Then, an interpretation beased on temporal dynamics is presented. Accordingly, the effect of characteristic parameters is surveyed. At the next step, nonlinear optical behaviors of optical bistability and modulation instability is investigated in 2D nanostructures (here: Graphene). Transform matrix method based on Maxwell equations is utilized for analyzing the optical bistability in the visible and terahertz frequency range. The method is insufficient to investigate the modulation instability. Hence, the predictor-corrector method is used to solve the nonlinear Schrodinger quation in order to investigate the unstable response of a system containing graphene layers dispersed inside a dielectic medium within a Fabry-Perot cavity. Finally, for the first time, the experimental observation of optical bistability and multi-stability is reported for graphene oxide and reduced graphene oxide suspension.
