We demonstrate an optical hitless wavelength-selective switch using a single microring resonator assisted with a symmetric Mach-Zehnder interferometer (MZI). A part of the ring waveguide and its symmetrical waveguide are designed to be an equally armed MZI as an on-off switch for the resonant state of the microring. The symmetric MZI is insensitive to the spectrum and it avoids free spectral range (FSR) matching or alignment in use. The FSR of the structure is 2.18 nm and the insertion loss (IL) at the drop-port is 1.8 dB. Our experimental results reveal that the fabricated device permits on-chip hitless rerouting of multi-wavelength signals, which means the intermediate wavelength remains unaffected during wavelength switching.

中文翻译：

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使用单个微环谐振器并辅以对称 MZI 的无中断波长选择开关


我们展示了一种使用单个微环谐振器并辅以对称马赫-曾德干涉仪 (MZI) 的光学无中断波长选择开关。环形波导的一部分及其对称波导被设计为等臂MZI，作为微环谐振状态的开关。对称 MZI 对光谱不敏感，可避免使用中的自由光谱范围 (FSR) 匹配或对准。该结构的 FSR 为 2.18 nm，分出端口的插入损耗 (IL) 为 1.8 dB。我们的实验结果表明，所制造的器件允许片上无中断地重新路由多波长信号，这意味着中间波长在波长切换期间不受影响。