光学 精密工程, 2016, 24 (2): 286, 网络出版: 2016-03-28
空气孔硅光子晶体偏振无关3 dB分光器
Polarization-independent 3 dB beam splitter in hole-type silicon photonic crystal
光子晶体 自准直效应 马赫-曾德尔干涉仪 偏振无关 分光器 photonic crystal self-collimation Mach-Zehnder interferometer polarization-independent beam splitter
摘要
提出并成功设计了基于自准直马赫-曾德尔干涉仪(SMZI)的空气孔硅光子晶体偏振无关3 dB分光器。介绍了采用偏振透射谱匹配的方法, SMZI可以实现偏振无关分束的基础理论。通过连续改变SMZI两臂的光程差, 基于匹配两个偏振的透射谱, 成功实现了在归一化频率下将TE偏振和TM偏振的入射自准直光束进行1∶1分光。最后, 利用时域有限差分数值模拟软件计算出来的TE偏振瞬时磁场分布图和TM偏振瞬时电场分布图验证了自准直光束的分光情况。结果显示: 如果将工作波长定在1 550 nm, 该偏振无关3 dB分光器大小仅为16.7 μm×16.7 μm。由于具有尺寸微小、结构简单并使用单一硅材料等特性, 该分光器有望应用于集成光路中。
Abstract
A Polarization-independent 3 dB Beam Splitter (PIBS) based on a self-collimation Mach-Zehnder Interferometer (SMZI) in a hole-type silicon photonic crystal (PhC) is proposed and successfully designed. According to theoretical analysis, it shows that the SMZI can implement the polarization-independent beam splitting by utilizing polarization transmission matching method. Then, by changing the path length difference of the SMZI continuously, the same splitting ratio 1∶1 of self-collimation beams for both transverse-electric (TE) modes and transverse-magnetic (TM) modes is obtained at the operating frequency of 0.177 4c/a based on matching two polarization transmission spectra. This behavior of the PIBS is also numerically demonstrated with the magnetic-field distribution for TE polarization and the electric-field distribution for TM polarization calculated by the time domain finite difference numerical simulation software. The results show that the dimension of the 3 dB PIBS is only 16.7 μm×16.7 μm when its working wavelength is at 1 550 nm. With its small dimensions, simple structure and single silicon material, this 3dB PIBS may have practical applications in future photonic integrated circuits.
陈曦曜, 林媛媛, 林贵敏, 傅平. 空气孔硅光子晶体偏振无关3 dB分光器[J]. 光学 精密工程, 2016, 24(2): 286. CHEN Xi-yao, LIN Yuan-yuan, LIN Gui-min, FU Ping. Polarization-independent 3 dB beam splitter in hole-type silicon photonic crystal[J]. Optics and Precision Engineering, 2016, 24(2): 286.