Tailoring the Radiation Pattern of Infrared Self-Complementary Nanoantennas With Ultrawide Impedance Bandwidth

A spiral self-complementary plasmonic nanoantenna has been designed to have constant input impedance within a wide frequency range, at least 50 to 300 THz. By covering the antenna with a glass cylinder of variable dimensions, its radiation pattern can be tailored without much effect on the constant input impedance. This approach can facilitate the design of broadly tunable nanoscale antennas that operate efficiently in the infrared region of the electromagnetic spectrum.