基于多模干涉1×4光分束器的优化设计

摘要

A novel photonic crystal 1×4 power splitter is designed in accordance with the self-imaging effect of multimode interference in the two-dimensional square photonic crystal, and the positions of four signle-mode output waveguides are determined by the positions of periodic twofold image, which are formed by the self-imaging effect of multimode interference. The identical output optical power in each output port of the device can be realized by inserting dielectric rod A and B in the junction between the multimode waveguides and lateral single-mode output waveguides. By simply tuning the radius of rod A and B, the energy proportionality of four output ports can be 0.01 dB, while the transmittance of this splitter be as high as 99.6%, and free distribution of energy can be achieved. Meanwhile, a large separating angle can be obtained with this structure.%设计了一种基于二维三角晶格光子晶体多模干涉效应的1×4分束器，根据多模干涉自映像效应，在二维光子晶体波导内交替出现双重像和单重像，由双重像的位置确定四个单模输出波导的位置。通过在侧向单模输出波导与多模耦合区域的连接处设置介质柱A、B，并有效调节介质柱A、B的半径，四端口均匀输出时均衡性为0.01 dB。该分束器透射率高达99.6%且输出能量可自由调节，还可实现光束的大角度分离。