基于电磁波在光子晶体耦合波导中的传输特性,建立了一个光开关模型。利用耦合模理论、 平面波展开法,计算耦合介电柱不同折射率时的耦合长度。以有限时域差分法为研究工具,分析介电 柱折射率为3和3.4时光波的输出状况,以及两种异质结构位置分布对光开关功能的影响。结果表明介 电柱折射率为3.4时改变光开关的功能,而异质结构位置分布不改变光开关的功能。利用此特性可以 在光开关的设计中有更多灵活性。

An optical switching model was established based on the transmission characteristics of electromagnetic wave in the photonic-crystal coupling waveguides. The coupling length was calculated when the refractive index of the coupling dielectric rods is in different values by using the coupling mode theory and plane wave expansion method. Using finite-difference time-domain method, the light wave output condition was analyzed as refractive index of dielectric rods equals to 3 and 3.4, and the effect of position of heterostructure to the optical switching functions was also analyzed. The result shows that the function of optical switching changes when the dielectric rods refractive index is 3.4, but the position of heterostructure doesn’t change the optical switch function. These properties can be used in the design of optical switches more flexibility in practice.