论文标题
时空表面等离子体极化子：一种新的繁殖不变的表面波数据包
Space-Time Surface Plasmon Polaritons: A New Propagation-Invariant Surface Wave Packet
论文作者
论文摘要
我们介绍了代表脉冲的表面波小包沿未完美的金属二极管接口传播的脉冲表面波数据包的独特类别的传播不变的表面等离子体极化子（SPP），并在所有维度上都定位 - 具有潜在的下波长横向横向空间宽度。这种无线性衍射的，无分散的“等离子子弹”的特征源于紧密的时空相关性纳入了SPP光谱支撑域中，因此我们称其为“时空” spps。我们表明，可以通过与任何材料特性独立于任何材料特性独立于时空场结构来调整时空spp波数据包的组速度。与传统的脉冲spp相比，我们提供了一个分析框架和数值模拟，以进行时空SPP的传播，这些脉冲spp的空间和时间自由度是可分开的，从而验证了前者的传播不变性。
We introduce the unique class of propagation-invariant surface plasmon polaritons (SPPs) representing pulsed surface wave packets propagating along unpatterned metal-dielectric interfaces and are localized in all dimensions - with potentially subwavelength transverse spatial widths. The characteristic features of such linear diffraction-free, dispersion-free `plasmonic bullets' stem from tight spatio-temporal correlations incorporated into the SPP spectral support domain, and we thus call them `space-time' SPPs. We show that the group velocity of space-time SPP wave packets can be readily tuned to subluminal, superluminal, and even negative values by tailoring the spatio-temporal field structure independently of any material properties. We present an analytical framework and numerical simulations for the propagation of space-time SPPs in comparison with traditional pulsed SPPs whose spatial and temporal degrees of freedom are separable, thereby verifying the propagation-invariance of the former.
