Field distribution of the Z2 topological edge state revealed by cathodoluminescence nanoscopy

• 作者: Xiao He Donglin Liu Hongfei Wang Liheng Zheng Bo Xu Biye Xie Meiling Jiang Zhixin Liu Jin Zhang Minghui Lu Zheyu Fang
• 来源期刊: 光电进展（英文版）
• 年，卷（期）: 2022,（4）
• 所属期刊栏目: Original Article
• 页码范围: 76-84
• 页数: 9页
• 语种: 英文
• DOI: 10.29026/oea.2022.210015

摘要

Photonic topological insulators with robust boundary states can enable great applications for optical communication and quantum emission, such as unidirectional waveguide and single-mode laser. However, because of the diffraction limit of light, the physical insight of topological resonance remains unexplored in detail, like the dark line that exists with the crys-talline symmetry-protected topological edge state. Here, we experimentally observe the dark line of the Z2 photonic topo-logical insulator in the visible range by photoluminescence and specify its location by cathodoluminescence characteriza-tion, and elucidate its mechanism with the p-d orbital electromagnetic field distribution which calculated by numerical sim-ulation. Our investigation provides a deeper understanding of Z2 topological edge states and may have great signific-ance to the design of future on-chip topological devices.