微弱旋转效应的圆柱形介质光波导耦合器的研究

Research on Circular Dielectric Optical Waveguides Coupler with a Weak Rotatory Effect

具有微弱旋转效应的两个平行圆柱形介质波导的微弱耦合是在矢量波动方程的基础上使用特异摄动法来解析的.对应于复合两个平行圆柱形介质波导系统的耦合模方程是满足麦克斯韦方程和边界条件的情况下得到的,此时摄动阶数限定在一阶范围内.可以发现具有微弱旋转效应的在两个平行波导的弱导内分别独立产生方向性耦合和偏振波的变换.方向性耦合是由耦合系数κ来控制,偏振波的变换是由耦合系数κ×来控制.

The evanescent coupling between two-parallel circular dielectric waveguides with a weak rotatory effect is analyzed by using a singular perturbation technique which is based on the vectorial wave formulation. The coupled-mode equations are derived in closed form which satisfies the Maxwell equations and boundary conditions for the composite dielectric waveguide system within the first-order perturbation. The directional coupling and polarization conversion take place separately in the weakly guiding two-parallel weak waveguides with a weak rotatory effect. The directional coupling is governed by the coupling coefficients κ, whereas the polarization conversion angle is controlled by the coupling coefficient κx.