基于光子晶体多模波导的1．31／1．55μm双波长功分器的设计

设计了一种基于光子晶体多模波导的双波长光功分器,该器件能同时实现1.31 μm和1.55μm两种通信波长的光信号功率的平均分配,整个器件长度仅为15μm,是已报道的常规结构的182分之一.根据导模传输法,讨论了对称入射时光子晶体多模波导中的自映像效应,采用时域有限差分法模拟了光场在波导中的分布,入射场的单重像和二重像交替在波导中周期性地出现.并讨论了功分器的输出效率,及输出效率随位于单模波导与多模波导联结处的介电柱位置变化而产生的变化.

Design of double-wavelength optical power splitters based on photonic crystal multimode waveguides

Based on photonic crystal multimode waveguides the double-wavelength optical power splitter is presented. The device can be used to divide the input beam equally for both 1.31 μm and 1.55 μm at the same time. The total length of this device is only 15 μm,which is one 182th of the conventional dielectric counterparts reported. On the basis of the guided mode propagation analysis method,the self-imaging effect is discussed for the case of symmetric incidence. The finite-difference time-domain method is used to simulate the propagation of the beam in the multimode waveguide. The results show that the repetitive appearances of single image and twofold image of the input field occur alternatively in this device. The efficiency of the splitter is calculated,and the variation of the efficiency corresponding to the positions of the dielectric rods lying at the junctions between the multimode waveguides and single-mode waveguide is also discussed.