光子晶体多路选择器的设计和仿真

Design and Simulation of Photonic Crystal Multiplexer

以时域有限差分法(FDTD法)和介质波导定向耦合理论为基础,模拟了光在光子晶体耦合器中的传输情况:当耦合器长度为拍长的整数倍时,光经过耦合沿输入波导输出;当耦合器长度为半拍长的奇数倍时,光经过耦合后从另一波导输出.我们设计了一个四端口的光子晶体多路选择器,实现了将3种不同波长的光进行分离.同时还提出了通过光子晶体耦合器的耦合长度来计算光波传输的群速度的方法.

The method of Finite Difference Time Domain （FDTD） and directional coupling theory of the medium waveguides are used as the basic theory. A field comes out through the input waveguide when the coupler length is an integer multiple of the beat length. In the contrast, the field injected into one waveguide switches entirely to the other one if the coupler length is an odd multiple of half the beat length. A three-wavelength photonic crystal multiplexer is designed. And a method to compute the group velocity by the coupler length is presented also.