We demonstrate a method for measuring on-chip waveguide losses using a single microring resonator with a tunable coupler. By tuning the power coupling to the microring and measuring the microring’s through-port transmission at each power coupling, one can separate the waveguide propagation loss and the effects of the coupling to the microring. This method is tolerant of fiber-chip coupling/alignment errors and does not require the use of expensive instruments for phase response measurements. In addition, this method offers a compact solution for measuring waveguide propagation losses, only using a single microring (230 µm×190 µm, including the metal pads). We demonstrate this method by measuring the propagation losses of silicon-on-insulator rib waveguides, yielding propagation losses of 3.1-1.3 dB/cm for core widths varying from 400-600 nm.

中文翻译：

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使用单点，两点耦合微环谐振器测量片上波导损耗

我们演示了一种使用带有可调耦合器的单个微环谐振器测量片上波导损耗的方法。通过调谐到微环的功率耦合并在每个功率耦合处测量微环的通过端口传输，可以分离波导传播损耗和耦合到微环的影响。这种方法可以容忍光纤-芯片耦合/对准误差，并且不需要使用昂贵的仪器来进行相位响应测量。此外，该方法仅使用单个微环（230 µm×190 µm，包括金属焊盘）即可提供用于测量波导传播损耗的紧凑型解决方案。我们通过测量绝缘体上硅肋形波导的传播损耗来证明这种方法，对于400-600 nm的纤芯宽度，其产生的传播损耗为3.1-1.3 dB / cm。