Dependence of anisotropic surface plasmon lifetimes of two-dimensional hole arrays on hole geometry

摘要

The dependences of surface plasmon lifetimes of two-dimensional Au hole arrays on aspect ratio, hole length, and depth have been studied by angle-dependent reflectivity. Long lifetimes can be obtained from the arrays by reducing the hole length and depth and increasing the aspect ratio. In addition, our results can be qualitatively discussed under the framework of coupled-charge model, indicating the interaction between holes can lead to an increase of surface plasmon lifetime. We believe such interaction can find applications in biosensing such as surface plasmon resonance spectroscopy.