聚合物微环谐振波分复用器传输特性的理论分析

根据耦合模理论,给出了1×N信道微环谐振波分复用器(MRRWM)的光强传递函数通用公式,并分析了微环谐振波分复用器的传输特性。利用参量优化结果,在中心工作波长约为 1.55μm、波长间隔约 5.6 nm的情况下,对1×8信道硅基聚合物微环谐振波分复用器进行了数值模拟。计算结果表明,该器件具有以下优良的性能:分波光谱准确,自由光谱区约为18 nm,对于半径10μm以上的微环弯曲损耗很小,且器件的插入损耗主要由波导的传输损耗决定,振幅耦合比率为0.2时对应的每条竖直输出信道的插入损耗在0.57 dB以下,信道间的串扰小于-18.5 dB,输出谐振峰3 dB带宽可达0.25 nm,最小背景光的强度约为3.8×10-4。

Theoretical Analysis for Transmission Characteristics of Polymer Microring Resonant Wavelength Multiplexer

The transmission characteristics are analyzed, and the general formulas of the transmission functions are presented for the microring resonant wavelength multiplexer (MRRWM) with 1×N channels in terms of the coupled mode theory. Using the results of parameters optimization, the numerical modeling is performed for a polymer MRRWM around the central wavelength of 1.55 μm with the wavelength spacing of 5.6 nm and 8 vertical output channels. The computed results show that the device has an exact output spectrum, the insertion loss is small and determined mostly by the transmission loss for microrings with radius R greater than 10 μm. For the case of the amplitude coupling ratio of 0.2, the device designed possesses some excellent features including the free spectral range of 18 nm, smaller insertion loss less than 0.57 dB, lower crosstalk below -18.5 dB, 3 dB-bandwidth of 0.25 nm, and weaker background intensity of 3.8×10-4 for every output vertical channel.