Metactronics: Lumped Elements in Optical Nanocircuitry
For many decades the well known concept of “lumped elements,” or standardized components such as resistors, capacitors, and inductors, revolutionized electrical engineering and has allowed for the modular construction of circuitry to this day. However, as we go to much higher frequencies and as we want to have faster circuits in the worlds of miniaturization, can we still have such lumped elements at the nanoscale that would use light instead of electricity?
That is what Nader Engheta, the H. Nedwill Ramsey Professor of Electrical and Systems Engineering and Professor of Bioengineering has suggested by devising a way to create lumped elements out of optical nanoparticles that harness light instead of electrons, a feat that could radically miniaturize electrical engineering in the coming decades. He has dubbed this new area of study “metactronics.”
What Engheta has done is to devise an optical nanocircuit “cookbook,” with recipes for nanoscale resistors, capacitors, and inductors. He is currently working on a formula for a switch, which would enable him to turn these circuits on and off.
Light would, Engheta says, be captured and focused into these nanoscale circuits by a material constructed to act as a “nanoantenna” much the same way that the internal antennas in our cell phones capture the appropriate signals for sending and receiving calls. He is currently investigating with his circuits via computer modeling, which show the output of the nanocircuits resembling the output of conventional circuits that we use today, but with optical signals. With this encouraging data, Engheta is moving into the fabrication of a proof of concept device.
It is amazing to consider the possible impact of these nanocircuits. Not only could they allow for extreme miniaturization and much higher data rate, but less electrical energy may be used to power them, leading to a smaller environmental impact from devices of the future.