Ichiji Naoki, Otake Yuka, Kubo Atsushi
Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba-shi, Ibaraki, 305-8571, Japan.
Faculty of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tenno-dai, Tsukuba-shi, Ibaraki, 305-8571, Japan.
Nanophotonics. 2022 Feb 25;11(7):1321-1333. doi: 10.1515/nanoph-2021-0740. eCollection 2022 Mar.
The spatiotemporal dynamics of a surface plasmon polariton (SPP) wave packet (WP) that interacts with a plasmonic nanocavity on a metal surface are investigated via femtosecond time-resolved two-photon fluorescence microscopy and numerical calculations. The nanocavity, which consists of a metal-insulator-metal (MIM) laminar structure (longitudinal length: ∼100 nm), behaves as a subwavelength meta-atom possessing discretized eigenenergies. When a chirp-induced femto-second SPP WP is incident on the nanocavity, only the spectral component matching a particular eigenenergy is transmitted to continue propagation on the metal surface. This spectral clipping induces a spatial peak shift in the WP. The shift can be controlled by tuning the eigenenergy or chirp.
通过飞秒时间分辨双光子荧光显微镜和数值计算，研究了与金属表面等离子体纳米腔相互作用的表面等离激元极化激元（SPP）波包（WP）的时空动力学。该纳米腔由金属-绝缘体-金属（MIM）层状结构组成（纵向长度：约100纳米），表现为具有离散本征能量的亚波长元原子。当啁啾诱导的飞秒SPP WP入射到纳米腔上时，只有与特定本征能量匹配的光谱分量会被传输，从而在金属表面继续传播。这种光谱剪裁会导致WP中的空间峰值发生移动。可以通过调节本征能量或啁啾来控制这种移动。
