本文研究了一种由三根并排放置的椭圆形金属-介质-金属纳米线构成的混合表面等离子体光波导所支持的电磁场基模的控制特性,中间是高折射率的介质纳米线,左右是两根对称放置的金属纳米线。研究结果表明,基模电磁场增强效应主要分布在三根纳米线形成的两个间隙区域,且对整个结构的几何参数有一定依赖性。因此,通过改变纳米线的几何尺寸、两根纳米线之间的间距以及介质的电磁参数,可以调整和控制这种波导所支持的基模的有效折射率、模式传输距离、归一化的模式面积和模式束缚因子等物理特性。基于这些有效的模式操控特性,这种混合型的表面等离子体光波导可以应用于高密度光子器件集成、纳米光子学和生物传感器等领域。
In this paper, the controlling properties of electromagnetic mode of a kind of surface plasmon waveguide (SPW) composed of center high refractive index dielectric nanowire with two metal nanowires place on both sides was investigated. All the nanowires cross-section was ellipse type. Results indicated that the electromagnetic field of the fundamental mode distributed mainly in the gap areas of the adjacent nanowires and was dependent on the geometry parameters of the structure. So, through adjusting the geometry parameters, one can manipulate and control the mode propagation properties, including mode effective index, propagation length, normalized mode properties,the studied waveguide can he applied to nanoscale photonic circuits and sensors.