摘要
基于表面等离子体的金属超材料存在欧姆损耗,使得它的谐振峰品质因子难以提高,从而影响了它的潜在运用,全介质超材料能够避免金属层的色散吸收和能量损耗,可以提高品质因子[1]。利用微纳结构的对称性破缺能够获得较高品质因子的谐振[2-4],促进了超表面在微纳光子学中的运用。本文设计了一种非对称的氮化硅全介质超表面,它能在可见光波段获得高品质因子的法诺谐振。这种非对称的结构能够产生磁偶极子,增强局域电场,达到捕获光的效果,此特性可用于增强氮化硅的非线性效应和二维材料的光致发光等。
引文
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