金孔阵列电介质与金电介质孔阵列的强透射特性

采用时域有限差分（FDTD）法研究了金膜厚度、电介质折射率及其厚度对金孔阵列电介质与金电介质孔阵列两种结构强透射特性的影响。研究发现这两种结构都具有较好的强透射特性，这表明光与金膜表面自由电子的电荷密度波耦合成表面等离子激元（SPP），对增强透射起到了关键作用。金膜厚度是影响强透射特性的主要因素，其衰减长度为35 nm；而与金膜相邻的电介质膜厚度对强透射特性影响极小。电介质折射率大小对强透射特性影响明显，折射率为1.8时能够获得较好的强透射特性。

Extraordinary Transmission Properties of Gold Aperture Array-Dielectric and Gold-Dielectric Aperture Array

The effects of gold film thickness, refractive index of dielectric and its thickness on extraordinary transmission properties of gold aperture array-dielectric and gold-dielectric aperture array are studied using the finite-difference time-domain (FDTD) method. The results show that both structures have a good extraordinary transmission property, which suggests that surface plasmon polariton (SPP), formed by coupling of light and free electron charge density wave of gold film surface, plays a key role in enhanced transmission. The gold film thickness is the major factor affecting the extraordinary transmission property, and its decay length is 35 nm; the thickness of dielectric film adjacent to the gold film has minimal impact on the extraordinary transmission property. The refractive index of dielectric has a distinct impact on the extraordinary transmission property, and the refractive index of 1.8 may lead to a good extraordinary transmission property.