Sierpinski fractal plasmonic antenna: a fractal abstraction of the plasmonic bowtie antenna

A new class of bowtie antennas with Sierpinski fractal features is proposed for sensing molecular vibration modes in the near- to mid-infrared. These antennas offer a compact device footprint and an enhanced confinement factor compared to a bowtie antenna. Through extensive simulations, it is shown that these characteristics are related to the ability of this fractal geometry to become polarized. Simulation results demonstrate that these antennas may be tuned between 700nm <= lambda <= 3.4 mu m and that electric field enhancement by 56 is possible at the center of the antenna gap. (C) 2011 Optical Society of America