线性啁啾型光纤光栅双稳特性的理论研究

Theoretically investigation on the bistability of linearly chirp nonlinear bragg grating

基于非线性耦合模理论,利用逆向递推传输矩阵方法,数值研究分析了线性啁啾型光纤光栅（LC-NLBG）的双稳开关性能。研究结果表明：在NLBG中引入啁啾能扩大实现双稳的入射光波长范围,当光栅啁啾参量发生变化时,光栅双稳开关性能表现出明显的差异,此差异源于啁啾光栅内部前向波能量分布的不同。

Based on the nonlinear coupled mode theory,by using the reversely recursive transmission matrix method,the switching characteristics of linearly chirp nonlinear Bragg grating（LC-NLBG） have been investigated numerically.The results show that,introducing chirp in fiber gratings is helpful to widen the bistable wavelength range;and the influence of the chirp on the switching-on threshold and the on-off ratio of the bistable switching are obvious,the chirp-dependent bistability is due to the difference of the axial distribution of forward wave intensity in the gratings.