Silicon photonic waveguide resonators, such as microring resonators, photonic crystal waveguide cavities, and Fabry–Perot resonators based on the distributed Bragg reflectors, are key device components for silicon-based photonic integrated circuits (Si-PIC). For the Si-PIC with high integration density, the device footprints of the conventional photonic waveguide resonators need to be more compact. Inverse design, which is operated by the design expectation and different from the conventional design methods, has been investigated for reducing the photonic device components nowadays. In this paper, we inversely designed the silicon photonic waveguide reflectors for two target wavelengths: one is 1310 nm and the other is 1550 nm. The silicon photonic waveguide reflectors have reflectance of 0.99993 and 0.9955 for the wavelength of 1310 nm and 1550 nm each with 5-μm-long reflectors. Also, we theoretically investigated Fabry–Perot resonators based on the inversely designed photonic waveguide reflectors. Q factors of the Fabry–Perot resonators have been calculated to be 1.3 × 105 for the wavelength of 1310 nm and 2583 for the wavelength of 1550 nm. We have expected that the inversely designed photonic waveguide reflectors and their applications for the Fabry–Perot resonators can be utilized for compact passive/active device components such as wavelength filters, modulators, and external cavity lasers.

中文翻译：

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紧凑型硅光子波导反射器的逆向设计及其在法布里-珀罗谐振器中的应用

硅光子波导谐振器，如微环谐振器、光子晶体波导腔和基于分布式布拉格反射器的法布里-珀罗谐振器，是硅基光子集成电路（Si-PIC）的关键器件组件。对于高集成度的Si-PIC，传统光子波导谐振器的器件占位面积需要更加紧凑。逆向设计是根据设计预期进行操作，与传统的设计方法不同，目前已经研究了减少光子器件元件的方法。在本文中，我们针对两个目标波长逆向设计了硅光子波导反射器：一个是1310 nm，另一个是1550 nm。硅光子波导反射器对于1310 nm和1550 nm波长的反射率分别为0.99993和0.9955，反射器长度为5μm。此外，我们还从理论上研究了基于反设计光子波导反射器的法布里-珀罗谐振器。问法布里-珀罗谐振器的因子经计算为 1.3 × 105波长为 1310 nm 时为 2583，波长为 1550 nm 时为 2583。我们预计反向设计的光子波导反射器及其在法布里-珀罗谐振器中的应用可用于紧凑型无源/有源器件组件，例如波长滤波器、调制器和外腔激光器。