Nader Engheta is fond of a line originally coined by George Bernard Shaw and used by Robert Kennedy in his presidential run: “Some people see things as they are and say, ‘Why?’ I dream of things that never were, and say, ‘Why not?’”
A scientist and an engineer, Engheta knows that the two occupations are inseparable. The Berwyn resident describes engineering as “the application of the laws of nature to make something new.” Driven by this simplified definition, Engheta has made unparalleled progress at the nanoscale, a dimensional range of 1-100 nanometers. To grasp this concept, consider that there are 25,400,000 nanometers in one inch, and a human hair is 80,000-100,000 nanometers wide. His focus has been on the modular assembly of optical nanocircuits, a unique set of “circuit alphabets” for electronics and optics. His work links and merges nanoelectronics and nanophotonics, enabling a two-way transfer of fundamental concepts between the two. Optical physicists can now tailor light-matter interactions based on Engheta’s nanocircuit alphabets, revolutionizing the fields of nanophotonics, materials science, electronics, and optical processing.
In 2006, Scientific American magazine named Engheta one of 50 “Leaders in Science and Technology.” A H. Nedwill Ramsey Professor at the University of Pennsylvania, he has affiliations in several departments, including electrical and systems engineering, physics and astronomy, materials science and engineering, and bioengineering. Collegues in the know see a Nobel Prize in his future. For that to happen, the political, diplomatic and scientific stars must all align for the Iranian-born scientist. As one insider puts it, recognition of “excellence without borders” is never automatic.
Born in Tehran, Engheta turns 65 in October. COVID-19 may interfere with plans for the scientific community to celebrate his birthday at an August conference in Calabria, Italy. A local event with family and close friends is scheduled for October at Penn. As a professor, Engheta stresses curiosity-driven research. “That’s how science grows,” he says. “That’s how my own interests and others’ interests evolve.”
He and his group of a dozen revolving Penn doctoral candidates and post-doctoral fellows operate with the shared belief that they can control electromagnetic light waves at the nanoscience level to open pathways to patents and products. They’re research involves a mindboggling array of disciplines and terms most of us have never heard of or could ever hope to completely grasp, including graphene optics, optical nanoengineering, microwave and optical antennas, fractional operators, and the physics and engineering of fields and waves. “If I control waves, I need materials,” Engheta says. “A microwave controls waves in a metallic box. I have one; everyone has one. But to do interesting and unique things, I need interesting materials. Metal could be interesting, but it’s already there—it exists.”
Among other things, Nader Engheta is the father of near-zero-index metamaterials. These manmade materials go beyond what’s found in nature, and they offer an infinite number of possibilities. “We can make properties that nature hasn’t given us, properties that individually are different and properties that together are different,” says Engheta. “With gold, we see gold. But at a nanoscale level, gold under a microscope radiates red and green. At that size, the small effects are what you see. At this point, we’re beyond doing science in the garage. It requires special equipment.”
To say Engheta’s research is trending would be an understatement. A recent Google Scholar name search shows 40,000 citations, with a rate of about 3,500 per year over the past five years. Wisely, Penn had him make a video to simplify his science for non-specialists. “It’s helped,” he says. “I talk to people who aren’t in the field who say they’ve listened—and now they’ve come to see.”
At home, Engheta’s wife, Susanne, has her own struggles with comprehending her husband’s work. “I hear it, yes. Do I understand it? That’s a different story,” she says. “His field is esoteric, but he’s able to explain it quite well. I listen, then after a while go and get tea. But I’m proud to have a husband who’s a forerunner in his field. We have a homemade genius.”
For Engheta, the endgame is application, which relies on functionality. He envisions metamaterials that “can do math with light”—nanoscale information processing. “If we can have a circuit that works with light—or waves—rather than electric current and voltage, we save money and energy in the end,” he says. “Because it’s smaller, eventually it’s cheaper and faster because it’s happening at the speed of light. And because it’s all smaller—a million times smaller—the information storage capacity is superior.”
Ultimately, Engheta would like to design a material that becomes a computer. “Not the same as we have now,” he says. “It exists.”
Computers have a storied history at the University of Pennsylvania, which was home base for the 1946 invention of ENIAC, the world’s first electronic computer. By the 1960s, just-as-bulky analog computers had appeared, but they were power hungry and not programmable. More than 50 years later, the goal of Engheta’s team is to perfect a metamaterial that essentially acts as a computer. “We’ve done it,” he says. “The next step is making it programmable.”
In the March 2019 issue of Science, Engheta debuted the experimental design structure for the first programmable analog computer at the micro and nanoscale level. The next task is to scale down the model. “It opens up the fields of material science, wave science, computer science,” Engheta says. “It’s how science grows.”
Engheta’s work could also improve image processing and edge detection for identification. Today, we need a probe to scan a field. In an ultrasound of a body area, a probe scatters the field it’s measuring. Pixels form so we can see it, “but it interferes with the cloaking,” Engheta says. “If the probe is invisible because you’re using metamaterial, it doesn’t scatter. Doing this with waves and without electronics, we’d essentially form a new type of lens.”
Engheta’s first brush with electrical engineering came at the age of 15 while looking over the shoulder of his brother as ihe toyed with a battery-operated transistor radio. It’s how he first learned about electromagnetic waves. “I always wanted to be a scientist,” he says.
Engheta was almost 23 when he emigrated from Iran to the United States in 1978 to study at the California Institute of Technology in Pasadena, Calif. The Iranian Revolution came that same year. “It was interesting timing,” says Engheta, who received his electrical engineering degree from the University of Tehran.
His first Christmas Eve away from home, Engheta met Susanne, who’d left Iran a year earlier. He earned his master’s and doctorate degrees at Caltech, remaining there for a fellowship year before spending the next four years as a senior research scientist at a Santa Monica, Calif., company. An offer from Penn prompted a move to the East Coast, and the couple had two children here. Sarah, a 27-year-old Wharton alum, is returning home from New York City to study software computer science at Penn. Alex, 30, is autistic, lives in a group home, and works two days a week through Baker Industries in Malvern.
As for their dad, he was the youngest of four brothers and a sister. One brother has died; the others live all over the world—none in Iran. Growing up before the revolution, his mother would be considered illiterate by today’s standards, though her son notes that she was extremely smart. Engheta’s father owned a hardware store. Both instilled the value of education. “My mother was always upset at her parents for not letting her go to school,” he says.
Engheta’s oldest brother, Nasser, is 92 and lives in Los Angeles. He remains a working TV journalist in an active Iranian community. “He’s always been like my father,” says Engheta.
At Caltech, Engheta was shepherded by the late Charles Papas, a legend in the field of electromagnetic waves. When the Iranian Revolution cut off communication between him and his family, Papas welcomed Engheta into his. “He said he would take care of me as long as he was alive,” recalls Engheta. “I now apply the same humanity to my students.”
Andrea Alù describes Engheta as a mentor, a scientific father and a hero. “I owe him a lot,” says the Rome-born scientist, who spent 2007-08 in a post-doctoral appointment at Penn and is currently teaming with Engheta in a federal project focused on low-energy electronic devices that work on light. “He changed my life in many ways. I didn’t know his field, but he welcomed me from beginning.”
And there were others. “He’s very open to helping junior scientists, and that’s very unique,” says Alù, a professor of physics and electrical engineering at City University of New York and the founding director of its Photonics Initiative. “Many scientists get to his level and get more selfish, only spending time with those who can help them. He’s accessible to everyone.”
Engheta is convinced that his work wouldn’t be appreciated in Iran. “There’s a different expectation,” he says.
He’s never been back home, and he declines to talk politics. But he can’t hide the sadness he harbors. “The United States is my country, but I feel sorry for the people [in Iran],” he says. “The government is horrible. There are so many talented young people, and if Iran was like any other country, we could help. But with Iran’s relations with the United States, no one can help from here. There’s no hope for a betterment between the two countries.”
“It’s too late for Iran,” his wife chimes in. “It’s a whole century behind.”
The Enghetas are big movie fans, and Susanne loves British novels. Her husband is a fan of political nonfiction, and he still nurtures an infatuation with the “Godfather” series. It’s a holdover from his days at Caltech, where he and other scientists had what Susanne calls a “cult obsession” with the films.
Despite their interest in travel and his fixation on waves, the two have never been to Hawaii. “When we lived in California, we were near Venice Beach, and we didn’t go,” says Susanne. “I guess we didn’t have aspirations to be beach bums.”
Engheta’s fascination with electromagnetic waves has crossed disciplines. As an assistant professor iat Penn, he received a call from Ed Pugh, then in Penn’s psychology department. Engheta was initially puzzled why a psychologist would be interested in his work. Then Pugh (who has since moved to University of California at Davis) introduced him to the green sunfish, a freshwater species he’d proven could polarize light like a human to see color, or shades of lightness and darkness. Since then, they’ve learned that human eyes are almost polarization-blind compared to invertebrates like bees, ants, octopus, squid and other marine species.
Engheta’s bio-inspired studies have led to the development of a camera that can see polarization of light in a way humans can’t. The camera can recognize a flat surface and capture a fingerprint, and that’s led to further research on fingerprinting.
For Engheta, it’s the intuition behind scientific inquiry that isn’t so easily explained. Read any 19th-century scholarly article and try to find even a glimpse of the human behind the scientist—let alone his failures. The written record reflects the research. “But we don’t see or hear about the struggles,” says Engheta.
History is often kind to scientists— and that should be the case for Engheta one day. “No doubt, if I had to prepare a nomination for him, I’d start in the next five minutes,” says Giuseppe Strangi, an interdisciplinary physicist working in nanophotonics at Case Western Reserve University in Cleveland. “I tell him, ‘Be ready my friend.’ He already has awards one after another. But if you ask me if he deserves [the Nobel Prize], no doubt.”
Strangi met Engheta at a 2009 conference. When their two fields merged, they began traveling in the same circles. The two are now collaborating to design metamaterials that can elevate (levitate) particles with light—another first. “We used to call each other ‘brother,’ and we feel we are,” Strangi says. “He remains genuinely humble.”
City University of New York’s Alù estimates that Engheta’s work will begin impacting products in five to 10 years. Today, energy used for computers in this country amounts to 10 percent or more of our total energy consumption. “It’s a huge problem,” Alù says. “If we move to the type of operations Nader is pioneering, they will require no energy or small amounts of energy, and they’ll be much more efficient.”
And if any of it leads to a prize? “That will come if it comes,” says Engheta. “I’m not saying this as a cliché, but when you have a ‘what if’ question, pose it and go after it—that’s what’s so interesting and satisfying. When I talk to inspire young scientists about curiosity, I say, ‘Ask questions without an application in mind. Application will come.’”