波导侧壁起伏对聚酰亚胺波导光学梳状滤波器串扰特性的影响及其改善方法

Crosstalk Caused by Fabrication Errors about Polyimide Waveguide Interleaver and its Improvement

提出了一种结构模型来分析由工艺引起的波导侧壁起伏对于聚合物波导光学梳状滤波器的滤波特性的影响。含氟聚酰亚胺高分子聚合物制备多级马赫曾德尔串联型光学梳状滤波器件的工作参量为中心波长1550 nm,波长间隔为0.8 nm,40通道的波长交错分离。模拟计算表明,对由高分子聚合物材料制备的多级马赫曾德尔串联型光学梳状滤波器件,其主要影响是增大了信道之间的串扰,中心波长1550 nm处的信道串扰由理想情况下的-40 dB降为-12 dB,极大地影响了器件的性能。在此基础上,提出一种改善光学梳状滤波器串扰性能的新结构,该结构由多级马赫曾德尔耦合器和微环共振滤波器串接构成,40个通道的串扰改善为-30 dB以下。

A simple model to analyse the influence of the random change of waveguide width caused by fabrication error on the spectral character of fluorinated polyimide Mach-Zehnder （M-Z） waveguide interleaver is presented in this paper. The working parameters of fluorinated polyimide Mach-Zehnder waveguide interleaver are the central wavelength of 1550 nm, wavelength interval of 0.8 nm, and 40 channels. The simulation calculation indicates that the main influence is the increase of the crosstalk among channels, the crosstalk of the central wavelength of 1550 nm is decreased from -40 dB to - 12 dB. Based on this result, we propose a new structure to improve the crosstalk performance of the device by cascaded micro-ring resonator filters, and then the crosstalk of 40 channels was decreased to less than -30 dB.