Epstein Itai, Suchowski Haim, Weisman Dror, Remez Roei, Arie Ady
Opt Express. 2018 Jan 22;26(2):1433-1442. doi: 10.1364/OE.26.001433.
We provide experimental and numerical demonstrations of plasmonic propagation dynamics in a multi-level coupled system, and present the first observation of plasmonic breathers propagating in such systems. The effect is observed both for the simplest symmetric case of a thin metal layer surrounded by two identical dielectrics, and also for a more complex system that includes five and more layers. By a careful choice of the permittivities and thicknesses of the intermediate layers, we can adiabatically eliminate the plasmonic waves in all the intermediate interfaces, thus enabling efficient vertical delivery and extraction of plasmonic signals between the top layer and deeply buried layers. The observation relies on controlling the excited mode by breaking the symmetry of excitation, which is crucial for obtaining the results experimentally. We also observe this breathing effect for transversely shaped plasmonic beams, with Hermite-Gauss, Airy and Weber wavefronts, that despite the oscillatory nature of propagation in such systems, still preserve all their unique wavefront properties. Finally, we show that such approaches can be extended to plasmonic propagation in a general multi-layered system, opening a path for efficient three-dimensional integrated plasmonic circuitry.
我们提供了多能级耦合系统中等离激元传播动力学的实验和数值演示，并首次观察到在这类系统中传播的等离激元呼吸子。在由两个相同电介质包围的薄金属层这一最简单的对称情形中以及在包含五层及更多层的更复杂系统中，均观察到了该效应。通过仔细选择中间层的介电常数和厚度，我们能够绝热消除所有中间界面处的等离激元波，从而实现顶层与深埋层之间等离激元信号的高效垂直传输和提取。该观察依赖于通过打破激发对称性来控制激发模式，这对于通过实验获得结果至关重要。对于具有厄米 - 高斯、艾里和韦伯波前的横向形状等离激元光束，我们也观察到了这种呼吸效应，尽管在此类系统中传播具有振荡性质，但它们仍保留了所有独特的波前特性。最后，我们表明此类方法可扩展到一般多层系统中的等离激元传播，为高效三维集成等离激元电路开辟了一条道路。
