不同非局域程度条件下空间光孤子的传输特性

光束在非局域非线性介质中传输由非局域非线性薛定谔方程描述.讨论了在不同非局域程度 条件下，空间光孤子的传输特性.提出了一个基于分步傅里叶算法数值求解孤子波形和分布 的迭代算法.假定介质的非线性响应函数为高斯型，得出了在不同非局域程度条件下空间光 孤子的数值解，并数值证明了它们的稳定性.结果表明，不论非局域程度如何，光束都能以 光孤子态在介质中稳定传输.光孤子的波形是从强非局域时的高斯型过渡到局域时的双曲正 割型，形成孤子的临界功率随非局域程度的减弱而减小，光孤子相位随距离线性增大，相位 的变化率随非局域程度的减弱而减小. 关键词： 非局域非线性薛定谔方程 空间光孤子 临界功率 相位

Properties of spatial optical solitons to different degrees of nonlocality

The propagation of optical beams in nonlocal nonlinear media is modeled by the nonlocal nonlinear Schrdinger equation.In this paper,discussed is the propagation properties of the optical spatial solitons in the media to different degrees of the nonlocality.An iteration algorithm based on the split_step Fourier method is presented to obtain the solutions of the solitons. The profiles of the solitons to different degrees of the nonlocality are numerically obtained in the assu mption that nonlinear response of the media is Gaussian. The stability of the so lutions is also demonstrated numerically,which shows that the stable solitons ca n survive to different degrees of nonlocality. The amplitude profiles of the sol iton transit gradually and continuously from a Gaussian function in the strongly nonlocal case into a hyperbolic secant function in the local case. The critical power for the solitons decreases as the nonlocality decreases. The weaker the n onlocality,the slower the soliton phase that has a linear relation with the prop agation distance increases.