Low-symmetry lattices of non-chiral meta-atoms for resonant handedness-preserving reflection
非手性超原子的低对称晶格用于共振手性保持反射
Anastasia Pozharkova, Oleg Blokhin, Sergey A. Dyakov, Denis G. Baranov
AI总结 本文通过数值和理论分析,研究了由高对称非手性超原子构成的低对称周期晶格(菱形和单斜晶格)实现共振手性保持反射的潜力,并分析了其鲁棒性。
详情
反射时保持光学辐射手性的镜子是设计众多具有对映体区分能力的共振纳米光子结构的基本构件。普通的金属和布拉格介质镜在此背景下不适用,因为它们会在法向入射附近反射时翻转电磁场的手性。尽管在开发此类反射结构方面取得了显著进展,但这一研究领域在很大程度上仍未得到探索。在这里,我们详细数值和理论分析了由高对称非手性超原子构成的低对称周期晶格用于手性保持(HP)共振反射的潜力。通过全波数值模拟,我们分析了一系列由圆形介质盘和/或孔组成的菱形和单斜(斜方)晶格,并在每个晶格中确定了近乎完美的HP反射区域。我们研究了这些结构对几何偏差、材料损耗和入射角的鲁棒性。最后,我们使用耦合模理论形式描述了这些结构的共振HP响应。
Mirrors that preserve the handedness of optical radiation upon reflection are an essential building block for the design of numerous resonant nanophotonic structures with capabilities for enantiomeric discrimination. Ordinary metallic and Bragg dielectric mirrors are not suitable in these context since they flip handedness of electromagnetic field upon reflection around normal incidence. While there has been considerable progress in the development of such reflecting structures, this research area remains largely unexplored. Here, we present a detailed numerical and theoretical analysis of the potential of low-symmetry periodic lattices composed of high-symmetry non-chiral meta-atoms for resonant reflection with handedness preservation (HP). Using full-wave numerical simulations, we analyze a family of rhombic and monoclinic (oblique) lattices of circular dielectric disks and/or holes, and in each identify the regime of near-perfect HP reflection. We study the robustness of these structures to geometric deviations, material losses, and incidence angle. Finally, we describe the resonant HP response of these structures using the coupled-mode theory formalism.