Chiral plasmonics and enhanced chiral light-matter interactions

Abstract

Chirality, which describes the broken mirror symmetry in geometric structures, exists macroscopically in our daily life as well as microscopically down to molecular levels. Correspondingly, chiral molecules interact differently with circularly polarized light exhibiting opposite handedness (left-handed and right-handed). However, the interaction between chiral molecules and chiral light is very weak. In contrast, artificial chiral plasmonic structures can generate "super-chiral" plasmonic near-field, leading to enhanced chiral light-matter (or chiroptical) interactions. The "super-chiral" near-field presents different amplitude and phase under opposite handedness incidence, which can be utilized to engineer linear and nonlinear chiroptical interactions. Specifically, in the interaction between quantum emitters and chiral plasmonic structures, the chiral hot spots can favour the emission with a specific handedness. This article reviews the state-of-the-art research on the design, fabrication and chiroptical response of different chiral plasmonic nanostructures or metasurfaces. This review also discusses enhanced chiral light-matter interactions that are essential for applications like chirality sensing, chiral selective light emitting and harvesting. In the final part, the review ends with a perspective on future directions of chiral plasmonics.

Ultrathin Suspended Chiral Metasurfaces for Enantiodiscrimination

“…However, the consequent signal is still in the millidegrees range. [39][40][41] Electron beam lithography (EBL) and focused ion beam (FIB) have also been widely used to fabricate chiral metamaterials at the nanoscale. For example, a few kinds of chiral metamaterials made by EBL or FIB, such as multilayer nanoarrays, [42][43][44][45] kirigami structures, [46] and chiral nanoholes arrays, [29,47] have demonstrated intriguing chiroptical features of giant CD, [48][49][50] excellent rotation of linearly polarized lights, [51] and helical dichroism.…”

Far-field detection of two-dimensional terahertz topological photonic crystals

“…拓扑绝缘体(Topological Insulators)作为一种在其 边界处支持能量传导、内部却表现为绝缘体的新型材 料是在凝聚态物理 [1][2][3][4][5][6][7] 近年来, 随着人工超材料 [8][9][10] 的发展, 为光学 [11][12][13][14][15] 和声学 [16,17] 类似的拓扑绝缘体发展奠定了基础. 最近, 拓扑绝缘体的概念已经扩展到光子学中 [18,19] , 各种各 样构建拓扑光子晶体(Topological Photonic Crystals)的 方法被提出.…”

Graphene-on-plasmonic slot waveguide photodetector

“…为解决光 电集成中光学和电学元件尺寸失配的问题, 基于硅基 光子学平台的表面等离子体结构 [3] 一直吸引着大批研 究者. 表面等离子体结构 [4][5][6][7][8] 能够把光场限制在突破光 学衍射极限的深度亚波长量级, 并在近场范围内实现 显著的场增强作用, 可以大大减小光器件尺寸进而实 现大规模光电集成. 另外, 其超小的尺寸结构可以大 幅减小载流子输运时间, 并具有超小的电容, 有潜力 实现THz量级的工作带宽 [9,10] .…”