November 12, 2019
Nader Engheta and his research team have designed the first prototype of an entirely new kind of computer: one that runs off of light rather than electricity. Once brought to the nanoscale, this technology could run computations much more efficiently and quickly than any digital computer that could ever be designed with existing transistor technology.
“We love waves. We are passionate about waves. Electro- magnetic waves, microwaves, optical waves,” says Professor Nader Engheta, introducing the wave-matter interaction research that his group does. Engheta’s passion for waves first arose as a child, watching his brother use a transistor radio. Now he applies waves to a variety of high-level research questions.
Engheta has designed a material that, when waves are sent through it, can solve equations or do analog computations. “We have done that theoretically and experimentally,” he says.
This success is just the beginning though. Many phenomena in science and engineering can be written in integral equations, so if Engheta’s material can solve equations, it has many potential applications.
“Whenever you have the possibility to compute something very fast and with small volume, it can be applied in many fields,” Engheta explains. Think of all the disciplines that involve nanoscale circuits, such as healthcare and tech.
Engheta is ambitious about how far he can take this research. While the analog computing is groundbreaking, the next step is to see if the material can learn from the computations, essentially transforming from an analog computer to one that has artificial intelligence.
And what if there were a way to do these computations with less energy? Computers were once large, energy-sucking machines. Nowadays, we tend to think of phones and laptops as relatively efficient, but their energy uses have been “offshored” in a sense, as huge amounts of energy are needed to power the servers for cloud-based computing. If Engheta’s technology is faster, and uses less energy, it could contribute to a major energy savings.
“There’s a very natural connection between this work and energy, as waves have energy.” Engheta says. Indeed, the waves lose little energy in the computation process and could also be “recycled,” resulting in ultra-low power wave-based computing systems.
To get to this point will take time. That said, Engheta notes that he never would have believed 30 years ago that he could make calls across the world using a phone the size of a cigarette box. Perhaps some day those phones will be analog.
Policy Challenge. Renewable Energy Certificates or Renewable Portfolio Standards require that distribution and generation companies produce a certain percentage of clean or renewable energy. The problem with policies such as Renewable Energy Certificates and Renewable Portfolio Standards is that they are percentage measures of an ever increasing whole. They chase a moving target. Renewable percentage standards must constantly increase if they are to maintain emissions reduction targets in a growing energy system, or new breakthroughs in energy efficiency, such as wave-powered computing, must be made.
The Numbers. Computational energy demand is projected to increase exponentially over the coming decades. By 2025, the information, communication, and technology sector could use up to 20 percent of all electricity and emit up to 5.5 percent of the world’s carbon. By 2040, this sector could consume as much energy as we use today across all sectors.
Further Reading. Total Consumer Power Consumption Forecast (Huawei Technologies) by Andrae Anders