双光子光折变介质中非相干耦合光伏孤子族

为了得到双光子非相干耦合光伏孤子族的结果,采用数值模拟方法,对稳态情况下多束互不相干的光束在双光子光伏光折变晶体中的传播进行了研究。结果表明:具有相同偏振和相同波长的多束互不相干的入射光束可在晶体中形成双光子非相干耦合光伏孤子族。当入射光束中仅包含两个分量时,孤子族就转化为光伏孤子对。并用双光子光伏光折变晶体Cu:KNSBN和LiNbO3进行了分析说明。研究结果可为空间光孤子理论的发展提供理论依据。     

带弱"平台"皮秒光孤子的数值研究

通过数值求解变系数非线性薛定谔方程,发现光纤系统对带有弱“平台”的皮秒光孤子有独特的传输特性。在常参数光纤系统中,这种光孤子体现“呼吸”特性,而在特殊的分布参数光纤系统中,则能较平稳地传输。     

球对称非谐势阱中玻色-爱因斯坦凝聚Gross-Pitaevskii方程的精确解

考虑了描述玻色 爱因斯坦凝聚的Gross-Pitaevskii(GP)方程, 得到了在球对称非谐势阱中玻色-爱因斯坦凝聚GP方程的精确亮孤子解。In this paper, we analyze Gross Pitaevskii equation which describes the dynamics of a bright soliton in trapped atomic Bose Einstein condensates, and obtain the exact bright soliton solution of Gross Pitaevskii equation in spherically symmetric non harmonic trap.     

暗孤子的周期性再生效应

通过数值求解变系数非线性薛定谔方程,讨论具有有限背景宽度的皮秒暗光脉冲的传输和相互作用。结果表明,一种新的效应,即暗孤子的周期性再生效应,稳定地存在于具有分布参量的光纤系统中,不会受到孤子间相互作用的影响。并且,这种再生效应对损耗和有限的扰动(如白噪声)等不敏感。这表明暗孤子的周期性再生效应是稳定的。     

双环芯微结构光纤特性分析

提出了一种由硅-空气孔作包层,两个环状掺杂区作芯的双环芯微结构光纤,并用有限差分法对它进行了分析.结果表明,基模电场能由弱到强地集中在双环掺杂的芯区,且环外较弱,环心最强.在1.55 μm波段,有较大色散,这在光纤色散补偿中将起到重要作用.     

Exact chirped multi-soliton solutions of the nonlinear Schr(o|¨)dinger equation with varying coefficients

In this letter, exact chirped multi-soliton solutions of the nonlinear Schrodinger (NLS) equation with varying coefficients are found. The explicit chirped one- and two-soliton solutions are generated. As an example, an exponential distributed control system is considered, and some main features of solutions are shown. The results reveal that chirped soliton can all be nonlinearly compressed cleanly and efficiently in an optical fiber with no loss or gain, with the loss, or with the gain. Furthermore, under the same initial condition, compression of optical soliton in the optical fiber with the loss is the most dramatic. Also, under nonintegrable condition and finite initial perturbations, the evolution of chirped soliton has been demonstrated by simulating numerically.     

Bragg空芯光纤中的群速度超光速的理论探讨

运用渐近法计算了多模B ragg光纤的场分布、有效折射率、各模式的色散参量、群速度及TE01模的能量速度。结果表明:各模式色散参量有正有负,但群速度都大于光速,而能量速度不大于光速。     

在孤子控制下两个飞秒光孤子间的相互作用

直接运用变系数高阶非线性薛定谔方程的精确2-孤子解,来研究在孤子控制下两个飞秒光孤子间的相互作用,讨论了邻近孤子的稳定性.结果表明联合控制群速度色散分布,三阶色散分布和非线性分布能抑制两个飞秒光孤子间的相互作用,而且能避免孤子超前或滞后,在特定的孤子控制系统下,两个飞秒光孤子有良好的稳定性.     

Propagation of light in （2＋1）-dimensional nonlinear optical media with spatially inhomogeneous nonlinearities

The （2＋1）-dimensional nonlinear SchrSdinger （NLS） equation with spatially inhomogeneous nonlinearities is investigated, which describes propagation of light in （2＋1）-dimensional nonlinear optical media with inhomogeneous nonlinearities. New types of optical modes and nonlinear effects in optical media are presented numerically. The results reveal that the regular split of beam can be obtained in （2＋1）-dimensional nonlinear optical media with inhomogeneous nonlinearities, by adjusting the guiding parameter. Furthermore, the stability of beam regular split is discussed numerically, and the results reveal that the beam regular split is stable to the finite initial perturbations.     

参数渐减光纤中孤子间相互作用的数值研究

从变系数非线性薛定谔方程出发,我们考虑了一种参数渐减光纤系统,并给出了皮秒孤子在该系统中相互作用的相对间距表达式.然后,采用数值模拟方法对皮秒和飞秒尺度下相邻孤子在该系统中的相互作用进行了详细的研究,并与均匀光纤中孤子间的相互作用进行了比较.结果表明:相邻孤子在参数渐减光纤中的相互作用比在均匀光纤中的相互作用相对较弱,选择适当的渐减系数有助于抑制孤子间的相互作用,提高光纤的传输比特率.