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Metamaterial-inspired nanoelectronics processes the deep subwavelength of light by a a form of optical circuitry. The optical circuitry is a tapestry of subwavelength nanometer-scale metamaterial structures and nanoparticles which may provide a mechanism for tailoring, patterning, and manipulating local optical electric fields and electric displacement vectors in a subwavelength domain, leading to the possibility of optical information processing at the nanometer scale.

Analogous to microelectronics
By exploiting the optical properties of metamaterials, these nanoparticles may play the role of “lumped” nanocircuit elements such as nanoinductors, nanocapacitors, and nanoresistors, analogous to microelectronics. Metamaterial-inspired nanoelectronics (“metactronics”) can bring the tools and mathematical machinery of the circuit theory into optics, may link the fields of optics, electronics, plasmonics, and metamaterials, and may provide road maps to future innovations in nanoscale optical devices, components, and more intricate nanoscale metamaterials.

Memory metamaterials
Memory metamaterials - One of the problems with most metamaterials is that they can only be designed to operate at a single "resonant" frequency. Although there are "frequency agile" metamaterials that allow their resonant frequency to be tuned with a certain stimulus, the tuning is lost as soon as the stimulus is taken away. Driscoll – whose group includes others from San Diego, Duke University in North Carolina, US, and ETRI in Daejeon, South Korea – solves this issue by creating memory metamaterials that can remember the new frequency that they should operate at.

Like many other metamaterials, memory metamaterials contain an array of conductive rings, called split-ring resonators (SRRs), which provide the basic electromagnetic properties. However, in memory metamaterials the SRRs are patterned onto vanadium dioxide, which has a metal-to-insulator phase transition that can be controlled with light or an applied voltage.

The journal Science article (on PDF) - The resonant elements that grant metamaterials their distinct properties have the fundamental limitation of restricting their useable frequency bandwidth. The development of frequency-agile metamaterials has helped to alleviate these bandwidth restrictions by allowing real-time tuning of the metamaterial frequency response. We demonstrate electrically controlled persistent frequency tuning of a metamaterial, which allows the lasting modification of its response by using a transient stimulus. This work demonstrates a form of memory capacitance that interfaces metamaterials with a class of devices known collectively as memory devices.

Novel electromagnetic properties
Novel electromagnetic properties are a variety of unique properties and functions as a result of the electromagnetic (EM) response of certain types of artificially constructed media. These types of properties are either not attainable or extremely difficult to achieve with naturally occurring materials.

Some of these novel electromagnetic properties are magnetism at optical frequencies, negative magnetic permeability, sub-wavelength resolution, reversed Cherenkov Radiation, inversion of Snell's law, and backward wave propagation.

Examples of two types of artificially fabricated media are metamterials and photonic crystals.

Photonics
Photonics - A rapidly evolving area of science and technology, photonics deals with the behavior of light considered in terms of streams of photons, rather than in terms of wavefronts subject to refraction and reflection as dealt with by the science of optics. A major application of photonics is in fiber optics, in which light instead of electrons is used to transmit information in auditory, visual, and digital forms.

Besides having the potential of carrying up to 100 times the information that electrons carry, photon-based equipment is inherently more compact, allowing for far smaller components. Development of high-speed photodetectors makes it possible to operate photonic telecommunications systems at frequencies of up to 50 billion hertz, or 50 gigahertz, five times that at which even the fastest modern electronic systems operate (and, at less than full efficiency, at frequencies up to 100 gigahertz). The result is a great increase in the amount of information that can be transmitted and great reductions in the time that transmission takes. The laser is basic to this and many other applications of photonics, including compact disc (CD) players and bar code scanners.

Harnessing Light
Harnessing Light: Optical Science and Engineering for the 21st Century. This book is available online for reading purposes. As we move into the next century, light will play an even more critical role—often the central role—in the ways we communicate, in the practice of medicine, in providing for the nation's defense, and in the tools we use to explore the frontiers of science. Optical science and engineering—or, more conveniently, just optics—is the diverse body of technologies, together with their scientific underpinnings, that seek to harness light for these and other tasks.

New fields of research
The new research fields of nanophotonics and metamaterials are closely interlinked. The term Nanophotonics was coined only a few years ago and is now a major research direction in optical physics and engineering. Driven by the dream of untapped device functionality, nanophotonics studies the exciting science of the interaction of light with nanostructures, at the size scale where optical, electronic, structural, thermal and mechanical properties are deeply interdependent. The aim is to control light in a minute device containing only a few layers of atoms using signals carried by only a few photons and to do it very fast, within only a few oscillation cycles of the light wave.

Indeed, in the last twenty years photonics has played a key role in creating the world as we know it today, with enormous beneficial worldwide social impact. Today it is impossible to imagine modern society without globe-spanning broadband internet and mobile telephony made possible by the implementation of optical fibre core networks, optical disc data storage (underpinned by the development of compact semiconductor lasers), modern image display technologies, and laser-assisted manufacturing.

The next photonic revolution will be explosively fuelled by a new dependence on active and switchable photonic metamaterials and nanophotonic devices. This significant revolution will lead to dramatic new science and applications on a global scale in all technologies using light, from data storage to optical processing of information; from sensing to energy conversion and defense. Also, other related research is listed here - Main Publications