We analyze a novel metal-coated fiber-optic platform for surface plasmon polariton (SPP) generation and interconnection. It is based on a metal-coated angled fiber facet (MCAFF), which enables alignment-free and unidirectional SPP generation from a fiber-optic mode with high conversion efficiency. We verify its functionality by means of both numerical simulation and preliminary experiment. We implement a two-level-thickness (TLT) configuration into the MCAFF to maintain its high optic-to-plasmonic conversion efficiency: The thin metallic layer just above the core region efficiently generates SPPs whilst the thick metallic layer beyond the core region enables its low-loss propagation by diminishing decoupling possibility into the dielectric region. We moreover devise a fiber-in-fiber-out (FIFO) platform that consists of a pair of TLT-MCAFFs. We numerically verify that it can yield more than 60% of FIFO coupling efficiency. We further show that the transmission spectrum of the FIFO-MCAFF is highly correlated with the refractive index of the top layer put on the metallic layer, and that it can be exploited to sensing applications that is required to measure and identify delicate changes in the refractive index of the top-layer material. We expect that the proposed metal-coated fiber-optic platforms will provide an efficient way to SPP generation and interconnection, and also has great potential to be novel sensing platforms for gas- or liquid-phase volatile substance.

中文翻译：

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用于表面等离子体激元产生和互连的金属涂层光纤平台

我们分析了一种用于表面等离子体激元 (SPP) 生成和互连的新型金属涂层光纤平台。它基于金属涂层成角光纤面 (MCAFF)，可从具有高转换效率的光纤模式中生成无对准和单向 SPP。我们通过数值模拟和初步实验验证了它的功能。我们在 MCAFF 中实施了两级厚度 (TLT) 配置以保持其高光到等离子体转换效率：位于核心区域上方的薄金属层有效地生成 SPP，而核心区域之外的厚金属层使其能够通过减少进入介电区域的去耦可能性来实现低损耗传播。此外，我们设计了一个由一对 TLT-MCAFF 组成的光纤输入光纤输出 (FIFO) 平台。我们通过数值验证它可以产生超过 60% 的 FIFO 耦合效率。我们进一步表明，FIFO-MCAFF 的传输光谱与金属层上的顶层的折射率高度相关，并且可以将其用于需要测量和识别折射率细微变化的传感应用。顶层材料的指数。我们预计所提出的金属涂层光纤平台将为 SPP 生成和互连提供一种有效的方式，并且也具有成为气相或液相挥发性物质的新型传感平台的巨大潜力。我们进一步表明，FIFO-MCAFF 的传输光谱与金属层上的顶层的折射率高度相关，并且可以将其用于需要测量和识别折射率细微变化的传感应用。顶层材料的指数。我们预计所提出的金属涂层光纤平台将为 SPP 生成和互连提供一种有效的方式，并且也具有成为气相或液相挥发性物质的新型传感平台的巨大潜力。我们进一步表明，FIFO-MCAFF 的传输光谱与金属层上的顶层的折射率高度相关，并且可以将其用于需要测量和识别折射率细微变化的传感应用。顶层材料的指数。我们预计所提出的金属涂层光纤平台将为 SPP 生成和互连提供一种有效的方式，并且也具有成为气相或液相挥发性物质的新型传感平台的巨大潜力。