Department of Physics, Tianjin Polytechnic University, Tianjin 300160, China.
Opt Lett. 2012 Dec 1;37(23):4919-21. doi: 10.1364/OL.37.004919.
This Letter presents a plasmonic nanostructure consisting of a nanodisk and a nanoring. The nanodisk is outside of the nanoring. The quadrupolar, hexapolar, and octupolar resonance modes of the nanoring are excited easily by the bright dipolar mode of nanodisks. This nanostructure shows strong interaction and deep Fano dips. In addition, the resonance frequency, depth, and line width of Fano dips can be tuned by changing the geometrical parameters of the nanodisk and nanoring. These plasmonic nanostructures show both high contrast ratio and high figure of merit. Such characters make them suitable for chemical and biological sensing.
这封信件介绍了一种由纳米盘和纳米环组成的等离子体纳米结构。纳米盘位于纳米环之外。纳米环的四极、六极和八极共振模式很容易被纳米盘的亮偶极模式激发。该纳米结构表现出强烈的相互作用和深的 Fano 凹陷。此外，通过改变纳米盘和纳米环的几何参数，可以调节 Fano 凹陷的共振频率、深度和线宽。这些等离子体纳米结构具有高对比度和高品质因数。这些特性使它们适用于化学和生物传感。
