The Planar Parabolic Optical Antenna

• Published in: Nano letters Vol. 13; no. 1; pp. 188 - 193
• Main Authors: Schoen, David T, Coenen, Toon, García de Abajo, F. Javier, Brongersma, Mark L, Polman, Albert
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 09.01.2013
• Subjects: Antennas; Broadband; Collective excitations (including excitons, polarons, plasmons and other charge-density excitations); Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Fullerenes and related materials; Holes; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Nanostructure; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Parabolic antennas; Parabolic reflectors; Physics; Plasmons; Surface and interface electron states; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Three dimensional; Visible and ultraviolet spectra; Wavelengths; nanophotonics; cathodoluminescence; Plasmonics; optical antennas; Nanometer scale; Plasmons; Nanostructures; Scaling laws; Visible spectra
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl303850v

One of the simplest and most common structures used for directing light in macroscale applications is the parabolic reflector. Parabolic reflectors are ubiquitous in many technologies, from satellite dishes to hand-held flashlights. Today, there is a growing interest in the use of ultracompact metallic structures for manipulating light on the wavelength scale. Significant progress has been made in scaling radiowave antennas to the nanoscale for operation in the visible range, but similar scaling of parabolic reflectors employing ray-optics concepts has not yet been accomplished because of the difficulty in fabricating nanoscale three-dimensional surfaces. Here, we demonstrate that plasmon physics can be employed to realize a resonant elliptical cavity functioning as an essentially planar nanometallic structure that serves as a broadband unidirectional parabolic antenna at optical frequencies.