光子晶体滤波分束双功能集成器件设计

Design of dual-function integrated device for photonic crystal filter splitting

摘要:

基于光子晶体环形腔与波导之间的共振耦合原理,设计了一款由环形缺陷和线缺陷组成的六端口二维光子晶体圆形晶格正方排列的双功能器件。运用平面波展开法(plane wave expansion method,PWEM) 和时域有限差分法(finite-difference time-domain,FDTD) 分析了该二维光子晶体器件的传输特性,得到了传输特性曲线和光场分布,然后讨论了环形腔中心柱内径和耦合区域的介质柱半径对输出端口滤波效率及透射率的影响。结果表明,通过调节环形腔中心柱以及耦合区域的介质柱参数,该器件可同时实现良好的滤波和分束功能。对于波长为1.510 μm和1.515 μm的输入光波,该器件主要具有滤波功能,滤波效率分别可以达到接近99.95%和93.27%；对于波长为1.490 μm的输入光波,主要具有分束功能,透射率最高可达99.74%。

Abstract:

Based on the resonant coupling principle between the photonic crystal ring cavity and the waveguide,a dual-function device of a six-port two-dimensional photonic crystal circular lattice with square arrangement composed of ring defects and line defects was designed.The transmission characteristics of the two-dimensional photonic crystal device were analyzed using the plane wave expansion method (PWEM) and finite-difference time-domain method (FDTD),and the transmission characteristics curve and light field distribution were obtained.Then,the influence of the inner diameter of the central column of the ring cavity and the radius of the dielectric column in the coupling region on the filtering efficiency and transmission rate of the output port was discussed.The results show that by adjusting the parameters of the center columns of the ring cavity and the dielectric columns in the coupling region,the device can simultaneously achieve good filtering and beam splitting functions.For input light waves with wavelengths of 1.510 μm and 1.515 μm,the device mainly has a filtering function,with filtering efficiencies of close to 99.95% and 93.27%,respectively.For input light waves with a wavelength of 1.490 μm,the device mainly has a beam splitting function,with a maximum transmission rate of 99.74%.