Computational Demonstration of Multiband Nanoantennas for Power Enhancement

We present multiband nanoantennas that can provide large enhancement factors at multiple frequencies in the optical spectrum. The structures are obtained by opening slits on the conventional bowtie designs. Since frequency/geometry scaling is not valid due to plasmonic properties of metals, two dimensional scans are performed using a rigorous solver based on surface integral equations and method of moments. The results demonstrate the feasibility of nanoantennas with multiband characteristics that can be useful in energy harvesting, bio-sensing, and optical imaging applications.