Multiple-valued characteristic research of nonlinear one-dimensional photonic crystal reflection spectrum

Based on the sublayer division and backward recursion algorithm, a simple and efficient numerical method for calculating the nonlinear reflection spectrum of one-dimensional photonic crystal with one kerr nonlinear defect layer was presented. The nonlinear reflection spectrum in the wavelength range of 1535 nm to 1565 nm was obtained by the method. When incident intensity is higher than the threshold, the defect mode moves slowly and appears inclined curved multiple-valued features at certain wavelengths. The influence of incident intensity on jump-up wavelength and jump-down wavelength was analyzed. The influence of parameters of periodic dielectric layer and nonlinear layer on reflection spectrum were investigated systematically. The results showed that the period, high-low refractive index ratio of periodic medium and the thickness of nonlinear defect layer is increased, the defect mode width is narrowed and the threshold of incident intensity, jump-on and jump-down wavelength is decreased. While when the third-order nonlinear coefficient is increased for nonlinear layer, the threshold of incident intensity is decreased and the defect mode width, jump-on and jump-down wavelength threshold is not changed obviously. The multiple-valued feature has an important role in the design of optical switch, optical filter, et al.