Near-Field Imaging and Time-Domain Dynamics of Photonic Topological Edge States in Plasmonic Nanochains
Near-Field Imaging and Time-Domain Dynamics of Photonic Topological Edge States in Plasmonic Nanochains
复制标题
等离激元纳米链中光子拓扑边缘态的近场成像和时域动力学
DOI：
10.1021/acs.nanolett.1c03324
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发表时间：
2021
期刊：
影响因子：
10.8
通讯作者：
and H. Misawa
中科院分区：
文献类型：
--
作者：
Q. Yan;E. Cao;Q. Sun;Y. Ao;X. Hu;X. Shi;Q. Gong;and H. Misawa
拓扑态的时域动力学演化性质在拓扑光子学的基础物理研究和实际应用中具有重要意义。然而，由于目前尚缺乏有效的超快时域动力学表征方法，研究大多集中在基于频域的特性上，而基于时域的特性研究报道较少。在这里，我们测量了金纳米链的等离子体拓扑结构的动态近场响应与配置的Su-Schrieffer-Heeger模型通过使用高时空分辨率的光电子显微镜。等离子体拓扑边缘态的退相时间随着体晶格数的增加而增加，体晶格数有阈值要求，最终达到饱和。我们通过模拟直接揭示了拓扑边缘态演化过程中存在一个瞬态体态，即能量在体晶格与边缘之间发生振荡弛豫。这为时域动态拓扑光子学的研究提供了一个新的视角。
Time-domain dynamic evolution properties of topological states play an important role in both fundamental physics study and practical applications of topological photonics. However, owing to the absence of available ultrafast time-domain dynamic characterization methods, studies have mostly focused on the frequency-domain-based properties, and there are few reports demonstrating the time-domain-based properties. Here, we measured the dynamic near-field responses of plasmonic topological structures of gold nanochains with the configuration of the Su–Schrieffer–Heeger model by using ultrahigh spatial-temporal resolution photoemission electron microscopy. The dephasing time of plasmonic topological edge states increases with increasing the bulk lattice number that has a threshold requirement and finally reaches saturation. We directly revealed through simulation that there is a transient bulk state in the evolution of topological edge states, that is, the energy undergoes relaxation from oscillation between the bulk lattice and the edge. This work shows a new perspective of time-domain dynamic topological photonics.