Optical antennas as nanoscale resonators

TL;DR

This paper reviews the development of optical antennas as nanoscale resonators that enhance light-matter interactions, enabling significant improvements in spontaneous emission rates across a broad spectrum.

Contribution

It introduces the concept of optical antennas functioning as nanoscale resonators, connecting their design principles with traditional radio-wave antennas and optical resonators.

Findings

Optical antennas can significantly enhance spontaneous emission rates.

They can operate effectively from ultraviolet to near-infrared wavelengths.

Optical antennas may serve as nanoscale resonators with unique advantages over microcavities.

Abstract

Recent progress in nanotechnology has enabled us to fabricate subwavelength architectures that function as antennas for improving the exchange of optical energy with nanoscale matter. We describe the main features of optical antennas for enhancing quantum emitters and review designs that increase the spontaneous emission rate by orders of magnitude from the ultraviolet up to the near-infrared spectral range. To further explore how optical antennas may lead to unprecedented regimes of light-matter interaction, we draw a relationship between metal nanoparticles, radio-wave antennas and optical resonators. Our analysis points out how optical antennas may function as nanoscale resonators and how these may offer unique opportunities with respect to state-of-the-art microcavities.