Wang Yan, Helmy Amr S, Eleftheriades George V
The Edward S. Rogers Sr. Department of Electrical and Computer Engineering University of Toronto, 40 St. George Street, Toronto, Ontario, M5S 2E4, Canada.
Opt Express. 2011 Jun 20;19(13):12392-401. doi: 10.1364/OE.19.012392.
We propose and investigate an ultra-wideband leaky-wave antenna that operates at optical frequencies for the purpose of efficient energy coupling between localized nanoscale optical circuits and the far-field. The antenna consists of an optically narrow aluminum slot on a silicon substrate. We analyze its far-field radiation pattern in the spectral region centered around 1550 nm with a 50% bandwidth ranging from 2000 nm to 1200 nm. This plasmonic leaky-wave slot produces a maximum far-field radiation angle at 32° and a 3 dB beamwidth of 24° at its center wavelength. The radiation pattern is preserved within the 50% bandwidth suffering only insignificant changes in both the radiation angle and the beamwidth. This wide-band performance is quite unique when compared to other optical antenna designs. Furthermore, the antenna effective length for radiating 90% and 99.9% of the input power is only 0.5λ(0) and 1.5λ(0) respectively at 1550 nm. The versatility and simplicity of the proposed design along with its small footprint makes it extremely attractive for integration with nano-optical components using existing technologies.
我们提出并研究了一种在光频下工作的超宽带漏波天线，旨在实现局部纳米级光学电路与远场之间的高效能量耦合。该天线由硅衬底上的一个光学窄铝槽组成。我们分析了其在以1550 nm为中心的光谱区域内的远场辐射方向图，带宽为50%，范围从2000 nm到1200 nm。这种等离子体漏波槽在中心波长处产生的最大远场辐射角为32°，3 dB波束宽度为24°。在50%带宽内，辐射方向图得以保持，辐射角和波束宽度仅发生微小变化。与其他光学天线设计相比，这种宽带性能非常独特。此外，在1550 nm处，辐射90%和99.9%输入功率的天线有效长度分别仅为0.5λ(0)和1.5λ(0)。所提出设计的多功能性、简单性及其小尺寸，使其在使用现有技术与纳米光学元件集成方面极具吸引力。
