Design and Characterization of High Efficiency Nanoantenna Couplers With Plasmonic Integrated Circuit

Four types of nanoantennas have been designed and characterized at 1.55 μm wavelength: Dipole antenna, Yagi-Uda antenna, dipole antenna array and bowtie antenna. The spectra, coupling efficiency, and far field radiation patterns are also investigated. We also quantitatively characterized the relationship between the couple-in efficiency and the spot size of the incident light. For the three dipole-type antennas, the couple-in and couple-out efficiencies have been measured experimentally. A plasmonic integrated circuit has also been designed and fabricated with these four types of nanoantennas. Direct and efficient optical coupling from an optical fiber into the plasmonic integrated circuit is demonstrated as well, and the couple-out efficiencies for these four nanoantennas are.