非均匀系统中非自治孤子的色散和非线性管理

基于包含自发拉曼散射和外电光调制效应的非自治非线性薛定谔方程,采用简单的变换方法,解析研究了三种非均匀系统中非自治孤子的管理和传输。结果发现,在非均匀的非线性渐增或色散渐减光纤系统中都存在精确的啁啾非自治孤子解,都可以实现孤子的放大和压缩,但具有不同的速度、频移和啁啾特性;而在非均匀的色散和非线性均渐减光纤系统中,可以支持无啁啾的非自治孤子,该孤子具有不变的脉宽和振幅以及振荡衰减的速度,孤子的频移仅由自发拉曼散射决定。同时,数值模拟结果进一步证实在三种非均匀管理系统中都可支持非自治孤子的传输。该研究结果为实际非均匀孤子管理系统中实现孤子的压缩和传输提供了理论依据。

Nonautonomous Solitons Under Dispersion and Nonlinearity Management in Inhomogeneous Systems

Based on nonautonomous nonlinear Schrodinger equation including self-induced Raman effect and external electrooptic modulation, the management and transmission of nonautonomous solitons in three inhomogeneous fiber systems are investigated analytically by a simple transformation. It is found that, both in inhomogeneous nonlinearity increasing and dispersion decreasing fiber systems, there exist exact chirped nonautonomous soliton solutions, which possess different velocities, frequencies and chirps, to achieve soliton amplification and compression. While in inhomogeneous fiber system with decreasing dispersion and decreasing nonlinearity, there exists chirp-free nonautonomous soliton solution with invariable pulse width and amplitude, oscillating decreasing velocity, and the frequency shift only depends on self-induced Raman effect. Simultaneously, numerical simulation results further verify that these three inhomogeneous management systems may support the transmission of the nonautonomous solitons. The obtained results provide a theoretical basis for achieving soliton compression and transmission in real inhomogeneous soliton management systems.