Recent progress on dielectric metasurfaces enables versatile flat optics designs including high-quality resonators. In this paper, we propose a high-quality resonator design based on asymmetric silicon metagratings in the near-infrared region. The design breaks the symmetry of a silicon subwavelength grating to manifest the dark mode of bound states in the continuum, resulting in a high-quality Fano resonance. Our numerical calculations indicate that its quality factor and peak wavelength are highly variable with different dimension parameters. Based on these results, we employ the metagrating resonator design for background index sensing with high sensitivity. Since it only consists of a glass substrate and a silicon layer of subwavelength thickness, this design can be a convenient platform for miniaturizing various resonator applications over large areas.

中文翻译：

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非对称硅迁移中的近红外Fano共振

介电超表面的最新进展实现了包括高质量谐振器在内的通用平面光学设计。在本文中，我们提出了一种基于近红外区域中不对称硅迁移的高质量谐振器设计。该设计打破了硅亚波长光栅的对称性，以在连续体中表现出束缚态的暗模，从而产生了高质量的Fano共振。我们的数值计算表明，其质量因数和峰波长在不同尺寸参数下变化很大。基于这些结果，我们将偏谐振器设计用于具有高灵敏度的背景索引感测。由于它仅由玻璃基板和亚波长厚度的硅层组成，