Wang Yulong, Ming Changjun, Zhang Yuquan, Xu Jie, Feng Fu, Li Ling, Yuan Xiaocong
Opt Express. 2020 Oct 26;28(22):33516-33527. doi: 10.1364/OE.405803.
Surface plasmon polariton (SPP) provides an important platform for the design of various nanophotonic devices. However, it is still a big challenge to achieve spatiotemporal manipulation of SPP under both spatially nanoscale and temporally ultrafast conditions. Here, we propose a method of spatiotemporal manipulation of SPP pulse in a plasmonic focusing structure illuminated by a dispersed femtosecond light. Based on dispersion effect of SPP pulse, we achieve the functions of dynamically controlled wavefront rotation in SPP focusing and redirection in SPP propagation within femtosecond range. The influences of structural parameters on the spatiotemporal properties of SPP pulse are numerically studied, and an analytical model is built to explain the results. The spatiotemporal coupling of modulated SPP pulses to dielectric waveguides is also investigated, demonstrating an ultrafast turning of propagation direction. This work has great potential in applications such as on-chip ultrafast photonic information processing, ultrafast beam shaping and attosecond pulse generation.
表面等离激元极化激元（SPP）为各种纳米光子器件的设计提供了一个重要平台。然而，在空间纳米尺度和时间超快条件下实现SPP的时空操控仍然是一个巨大的挑战。在此，我们提出了一种在飞秒光散射照射的等离子体聚焦结构中对SPP脉冲进行时空操控的方法。基于SPP脉冲的色散效应，我们在飞秒范围内实现了SPP聚焦中波前的动态控制旋转以及SPP传播中的重定向功能。数值研究了结构参数对SPP脉冲时空特性的影响，并建立了一个解析模型来解释结果。还研究了调制后的SPP脉冲与介质波导的时空耦合，展示了传播方向的超快转向。这项工作在片上超快光子信息处理、超快光束整形和阿秒脉冲产生等应用中具有巨大潜力。
