1 闽江学院 物理学与电子信息工程系, 福建 福州 350108
2 福建师范大学 光电与信息工程学院, 福建 福州 350007
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。
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
Author Affiliations
Abstract
1 College of Photonic and Electronic Engineering, Fujian Normal University, Fuzhou 350007, China
2 Department of Physics and Electronic Information Engineering, Minjiang University, Fuzhou 350108, China
A tunable dual-band infrared polarization filter is proposed and investigated. Based on the perfect absorption characteristic of the metal-dielectric-metal sandwich structure, the reflection spectrum performs as a filter. The filter consists of three layers. The top layer is a compound metal nano-structure array comprised of rectangular strips. The middle and bottom layers are a dielectric spacer and metal film, respectively. The calculated results show that the filter properties are closely related to the polarization of the incident light. Different dual-band wavelengths are filtered while the incident light has different polarizations, which are parallel or vertical to the x axis. Moreover, it is found that the resonant wavelength strongly depends on the length of the rectangular strip (which causes the resonant effect) and is independent of other strips. Therefore, the filter wavelengths can be tuned freely by adjusting the length of the corresponding rectangular strip. In addition, the calculated results show that all of the intensities at the filter wavelengths are closed to zero, which implies that the filter exhibits good filtering performance.
130.0130 Integrated optics 130.7408 Wavelength filtering devices 130.3990 Micro-optical devices Chinese Optics Letters
2015, 13(3): 031301
