Analysis of the Effective Refractive Index of Silicon Waveguides Through the Constructive and Destructive Interference in a Mach–Zehnder Interferometer
Analysis of the Effective Refractive Index of Silicon Waveguides Through the Constructive and Destructive Interference in a Mach–Zehnder Interferometer
复制标题
通过马赫-曾德尔干涉仪中的相长干涉和相消干涉分析硅波导的有效折射率
作者：
Y. Dattner;O. Yadid
本文介绍了一种通过马赫-曾德尔干涉仪(MZI)中的相长干涉和相消干涉测量硅波导和更大尺寸的波导的有效折射率之间的增量的方法。该方法包括固定的有效折射率变化，通过将干涉仪中的一只臂逐渐减小到更宽的波导尺寸来合并。MZI由一个Y分支分路器和一个多模干涉(MMI)耦合器组成。Y分支分光器将输入光50/50分成两个臂，MMI用于两个臂的复合。干涉仪中一臂的有效折射率相对于另一臂的有效折射率的变化将在MMI中引入复合的相位差。MMI具有以下三个端口：顶部和底部输出端口，它们是反对称输出，以及中间端口，它们是对称输出。当两个信号同相时，所有光被耦合到对称端口，并且当两个输入是π异相时，光被50/50耦合到反对称端口。该干涉仪是在绝缘体上硅(SOI)晶片上设计的，由比利时IMEC制造。给出了理论结果、仿真结果和测量结果，并进行了比较。
This paper introduces a method of measuring the delta between the effective refractive index of a silicon waveguide and a waveguide with wider dimensions through the constructive and destructive interference in a Mach-Zehnder interferometer (MZI). The method consists of a fixed effective refractive index variation incorporated by tapering one of the arms in the interferometer to a wider waveguide dimension. The MZI consists of a Y-branch splitter and a multimode interference (MMI) coupler. The Y-branch splitter splits the input light 50/50 into the two arms, and the MMI is used for recombination of the two arms. A change in the effective refractive index of one arm in comparison with the other arm in the interferometer will introduce a phase difference on recombination in the MMI. The MMI has the following three ports: the top and bottom output ports, which are the antisymmetric outputs, and the middle port, which is the symmetric output. When the two signals are in phase, all the light is coupled into the symmetric port, and when the two inputs are π out of phase, the light is coupled 50/50 into the antisymmetric ports. The interferometer is designed on a silicon-on-insulator (SOI) wafer and fabricated through IMEC Belgium. Theoretical, simulation, and measured results are presented and compared.