Fabrication and Optical Characterization of Bowtie Antennas

The pressing need for energy conversion devices with higher efficiency and the pursuit for nano-scale sensing have called for intense research in the use of plasmonic nanostructures. In this work, we discuss fabrication and characterization of bowtie antennas with gaps down to 10 nm for optical frequencies. With structures as simple as equilateral triangles, we observed an extinction cross section of ten times the geometrical cross section, which is twice the value previously reported. Finally, we measured the scattering profile of a series of bowtie antennas with increased size using confocal microscopy.