Nanonetworking in the Terahertz Band and Beyond

The possibility to control matter at the atomic and molecular scale opens the door to new types of devices that exhibit unprecedented physical properties. For the wireless communications community, the development of miniature transceivers and antennas that operate in traditionally uncharted frequency bands of the electromagnetic spectrum opens the door to transformative applications across scales (from nano to macro), domains (biological and non-biological), and realms (from classical to quantum). In this article, the state of the art in electromagnetic nanoscale communication and networks is presented by following a bottom-up approach. After describing some innovative applications of this technology, the fundamental physical properties and capabilities of nano-transceivers and nano-antennas at optical and terahertz frequencies are reviewed. The main phenomena affecting the propagation of the generated signals are then presented both from the wave and particle perspectives. Starting from the hardware capabilities and the channel peculiarities, tailored communication and networking solutions are discussed, all defining a roadmap to transform fundamental research into socially-meaningful applications.