光波导微环谐振器用于二进制格式变换研究

摘要

Based on the linear property of silicon microring resonators, we experimentally observed that such resonator can transform square-wave signal into pulse-wave signal, and the output waveform is strongly dependent on the input wavelength. We then proposed a mathematical model, which utilized linear coupling mode theory, Fourier transform and electro-optical Mach-Zehnder (MZ) intensity modulation functions. The numerical simulation results fit well with the experimental results. Besides, we gave a detailed explanation based on the transfer function of microrings. Furthermore, we have studied the case when the ring resonator is deviated from the critical coupling condition, and found that the coupling state, over coupling or under coupling, can be easily judged through the output waveform.%实验观测到了微环对入射二进制码的格式转换作用，且这种转换作用对入射光波长具有强烈的依赖关系。使用线性耦合模理论，结合傅里叶变换以及电光马赫曾德强度调制作用，理论再现了这一实验结果，并通过使用简化的传递函数对此进行了解释。理论分析还表明，对于非临界耦合微环，通过格式转换后波形的非对称性可以直观地判断微环的耦合状态，即过耦合或欠耦合有不同的输出波形特点。