Das Ritwick, Jha Rajan
Carrer de la Coruna, 13, Mediterranean Technology Park, 08860, Castelldefels, Barcelona, Spain.
Appl Opt. 2009 Sep 10;48(26):4904-8. doi: 10.1364/AO.48.004904.
A detailed mathematical analysis along with a theoretical model for the modes supported at the interface of a metal and periodically stratified medium (Bragg structure) is presented. The modes that are supported at the interface of a plasmon active metal (such as gold) and a Bragg structure are commonly known as surface plasmon-Bragg modes. We found that these modes have effective indices lower than any of the material indices of the layers comprising the Bragg structure, and they are highly dispersive when compared to the conventional surface plasmon modes that are supported at the metal and dielectric interface. The plausible physical explanation behind the strong dispersive behavior of the surface plasmon-Bragg mode is provided. Finally, the comparison of dissipation loss for the surface plasmon-Bragg modes is investigated and it has been shown that there is more than fivefold enhancement in the magnitude of propagation lengths as compared to the conventional surface plasmon mode.
本文给出了一种详细的数学分析以及金属与周期性分层介质（布拉格结构）界面处支持模式的理论模型。等离子体活性金属（如金）与布拉格结构界面处支持的模式通常称为表面等离子体 - 布拉格模式。我们发现这些模式的有效折射率低于构成布拉格结构的各层材料的任何折射率，并且与金属和电介质界面处支持的传统表面等离子体模式相比，它们具有高度色散性。文中给出了表面等离子体 - 布拉格模式强色散行为背后合理的物理解释。最后，研究了表面等离子体 - 布拉格模式的耗散损耗比较，结果表明与传统表面等离子体模式相比，传播长度的大小增强了五倍以上。
