We present a theory to investigate the existence and the propagation properties of incoherently coupled single-hump and dipole soliton pairs in self-defocusing media with parity-time symmetric lattice. These soliton pairs can exist provided that they are composed of two optical beams with the same polarization and wavelength. It is found that single-hump soliton pairs are always stable when the components copropagate in the lattice, whereas high-power dipole soliton pairs are unstable. If one of the components is absent, the propagation behavior of the other one is also studied.

假设介质是中心对称的，并考虑入射场与感应场同介质相互作用，在经典力学框架内，把介质的运动方程化为双频激励下的Duffing方程，用多尺度法揭示了拉曼谱的复杂结构。分析了系统的倍频共振和组合共振。结果表明，在拉曼线两侧出现了很多伴线，而且这些伴线的强度是彼此不同的；指出了可以利用共振效应，通过适当的参数选择或介质选择就可获得强的激光输出。

在经典力学框架内和位错线整体运动的假设下，把Seeger方程化为具有固定力矩的摆方程。引入相面积概念描述了位错的能量转移和释放机制，并导出了能量释放系数。分析表明，同宿轨道很难完成能量传递，周期轨道也不能实现大范围内的能量转移。但是，只要适当控制超晶格的生长温度和速度，就可实现系统能量的有效释放。