An inside look at the radiation-sensing material that’s on the Pentagon’s radar

In Overmatched, we take a close look at the science and technology at the heart of the defense industry—the world of soldiers and spies.

BACK IN 2008, the Navy had a problem with an aging version of its F/A-18 fighter jet: A crack had appeared on a plane’s wing, and officials thought the issue might not be isolated to this one aircraft. The military branch set out to inspect hundreds of its pricey jets for this same structural issue.

Nobody wants a fracture in the wing of their aircraft. Or, you know, anywhere on an aircraft. Catching and diagnosing issues like these is one idea motivating a new company called RadiantNano. Co-founders Matthew Alpert and Leslie Dewan want to make radiographic imaging—using radiation to make pictures—easier, cheaper, and literally more flexible. They’ve created a technology that uses a novel material called Novskite to do just that—it could basically take an X-ray of the aforementioned aircraft and catch such structural issues. What’s more, the material can also identify the presence of ionizing radiation (that’s the scary kind of radiation) and reveal the characteristics of its source.

“Radiation is this very powerful and exceptionally underutilized tool for seeing the world around us,” says Dewan. The idea is that through the invisible, more of the world becomes knowable.

The Department of Defense is interested in that vision. Earlier this year, RadiantNano was selected to take part in the National Security Innovation Network’s (NSIN) Propel program—which gives early-stage companies access to DOD bigwigs and can help them tweak their technology toward military applications. 

There’s a spectrum of reasons that the military might be interested in getting an image of the inside of, say, a shipping container. Or knowing if radiation is present, and if so, what’s causing it. Technology like RadiantNano’s could be useful not just for checking jet airframes for cracks, but trucks for dirty bombs. At the same time, you may encounter their innovation at a future doctor’s visit if you fall off your roller skates. RadiantNano is, in other words, trying to give soldiers and spies what they want—while providing something useful to civilians too. 

A scintillating beginning 

RadiantNano got its start partly because its founders wanted to boost not just image-making but also radiation detection and identification—improving a set of tools that has existed for more than a century. You’re probably familiar with the old click-click-click of Geiger counters. But those kinds of devices aren’t the only game in town anymore. One of several options for a radiation-hunter is a type of material called a scintillator. Scintillators alert humans to energetic emissions in a different way: They emit their own light, which photodetectors inside the device then pick up and translate into information. The characteristics of that light—its brightness, the particular wavelengths it’s pumping out—reveal what type, and what level, of radiation is lurking around. That’s how Novskite works, lighting up with visible light when X-rays hit it. But unlike some other scintillators, the novel material is sensitive, high-resolution, and relatively inexpensive. It also doesn’t rely on rare-Earth minerals that often come from countries the DOD doesn’t want to deal with (such as China) and which, like toilet paper, can also be subject to supply chain disruptions. 

In detector form, an approach that RadiantNano initially pursued, the company’s tech works like scintillation detectors of old, translating that light into information internally. But the material can also be molded into a thin, flexible sheet—a high-tech Fruit Roll-Up—that makes it easy to deploy. In that form, the material is useful for imaging, and can act like X-ray film. 

Here’s how it works: Couple the scintillator with an array of photodiodes and shine X-rays at it. It will absorb those and re-emit visible light, which the photodiodes will then pick up and turn into a digital image. If you put an object between the X-ray source and the scintillator, the digital image will show an X-ray-vision picture of that object. Because RadiantNano’s stuff is more sensitive than the stuff your physician currently has, you’d get a lower dosage of X-rays than is currently required to diagnose your broken ankle. 

In that way, it could also take radiographic images of, say, vehicles crossing the border into the US. When the company began, they were also interested in using the detector form of the scintillator to pick up and identify sources of radiation that might be wheeling their way into the country.

That’s big business for the US government. Just ask scientist Richard Kouzes, an emeritus researcher at the Pacific Northwest National Laboratory. He has been in the hazardous detection industry for around half a century, working both on basic science and on national security applications. The Pacific Northwest National Laboratory heads up the deployment of radiation detectors at US borders on behalf of the Department of Homeland Security, and Kouzes was initially the scientist in charge of specifying the requirements for such devices at all crossings. “If you drive across the Canadian border or the Mexican border, you may see these big yellow pillars,” he says. Those are the fruits of the program he worked on, meant to make sure people aren’t smuggling nuclear or radiological material in or out.

Such devices have come a ways since the field started around 130 years ago, when Henri Becquerel first discovered that radiation existed. Geiger counters clicked onto the scene in the early 1900s. But detectors haven’t necessarily improved as much over the years as you’d think. “It’s been what I would consider a relatively slow evolution of technology,” says Kouzes.

Of course, better materials have come along, and so have better electronics, making instruments of various types more sensitive, their results more detailed, and their designs more flexible. “There’s always a push to do better,” says Kouzes.

Still, he continues, “a lot of the detectors that are used today still have roots in some of those old detection technologies.” And there’s room—and money—for improvement, at least in the national-security sector, where questions and concerns abound.

Worst-case scenarios go like this: Maybe someone’s schlepping cobalt-60 over the Canadian border. Maybe a shipping container has surprise cargo, like a dirty bomb. 

Meanwhile, the International Atomic Energy Agency has to inspect and monitor nuclear power plants and other reactors, along with stockpiles of substances like plutonium, to make sure everybody has the amounts and types of dangerous material they’re supposed to, and not a secret weapons program. 

The solar sell 

Some of those thorny problems were compelling to the company as it got its start. But Alpert, co-founder and chief technology officer at RadiantNano, and a chemical engineer by training, didn’t intend to get into the radiation detection business at all. Instead, he started out in the radiation conversion business—changing the sun’s rays into electrical energy. 

As a graduate student at the University of Virginia in the 2010s, he was toiling away on next-generation solar cells, trying to make them more usable and efficient. Alpert had helped invent a new material that could potentially accomplish both those goals. It was a modified version of perovskite, the name for a crystal structured like a diamond embedded in a cube with a core. Perovskite crystals, of various compositions, are a favorite replacement for silicon in solar cells. But Alpert’s was different, because he’d added nanoparticles to the regular recipe, a sprinkling he hoped would up its game. The configuration and composition that the company now uses is called Novskite, a name Alpert gave the material.

It was an interesting idea, but there were obstacles to commercialization. And so, like any good soon-to-be-startup-founder, he pivoted. “Turns out that a lot of the things that make a material good for solar cells actually make it good for radiation detection as well,” he says. He became part of a startup accelerator, joined up with Dewan, and was on the way to seeing the world differently.

At the beginning, the team wasn’t overly familiar with why the military might be interested in their scintillator. Their technology—and all technology the National Security Innovation Network supports—is called “dual-use,” meaning it has a use for regular civilians and a use for the military. It was only when a colleague at the Department of Homeland Security got in touch that one of Novskite’s potential defense uses came into focus. The contact said that he needed a new radiation detector for border security, as Alpert recalls, and wanted to know if they could help. 

“And it turns out, we figured out we could,” says Alpert.

Current border detectors work a little like metal detectors, he continues. You go through them, and if they detect radiation, they say so. But they give a yes-or-no, binary answer. But not every “yes” means “danger.” Bricks, concrete, and bananas also blast radiation out. So do granite countertops. But the information coming out of RadiantNano’s scintillation device would both detect radiation and show the unique fingerprint of different emissive substances, so officials could tell the difference between kitty litter and uranium.

That’s the “detector” version of RadiantNano’s toolset, and part of the company’s original vision. 

“Our material has a lot of potential benefits when being used for detection,” says Dewan. “But as we developed it, we realized that we’re also well-suited to radiographic imaging, which is a much larger market. The majority of our work now focuses on imaging applications.”

That’s perhaps still useful at the border, and in defense more broadly. A radiographic image of the inside of a truck driving into, say, Buffalo could provide insights into its cargo. An X-ray shot of a ship, on the other hand, could show a crack in the hull before it gets too big and makes the ship sink. On the flip side, a RadiantNano imager could scan you to see if your bones have cracks. 

Looking for defensive angles

The National Security Innovation Network was into the company and its tech’s potential applications, selecting RadiantNano as one of 16 startups in its Propel cohort this year, and setting them up for guidance and mentorship. 

NSIN itself started up in 2016, and it exists today as a component of the Defense Innovation Unit, and also under deputy managing director Justin Dunnicliff. Its goal is to help small companies navigate defense contracting. “There’s really not a clear pathway,” Dunnicliff says.

That’s because the problems the DOD needs to solve can be opaque—invisible, perhaps—if you are not yourself the DOD. “Everything is classified, even if it’s not really a classified problem,” Dunnicliff says. “The DOD is huge and labyrinthine. How do you even find the right office to talk to?”

Programs like Propel help bond startups to the right offices, and break the ice between government offices and the small companies’ coworking spaces and academic buildings.

To do that at all, though, NSIN first has to find the innovators it desires. “We need to be present in the communities that we want to engage with,” Dunnicliff says—namely, colleges that spit out people like Alpert, who spit out technology companies. “We would embed people at universities,” Dunnicliff says. He himself hunkered down at the University of Washington for a while, learning about what researchers were up to, and brainstorming how that work might be slanted to help the DOD.

That’s not always something academics are aware is even a possibility. “Everyone in DC knows about working for the Department Defense, the national security sector,” he says. “But you get to the West Coast, and it’s not as readily apparent for them, what the opportunities are, whether it’s even a thing that they want to do.”

A lot of people are interested in exploring it, Dunnicliff says, because it’s a new and novel set of problems, and scientists love that stuff (the fact that the DOD gets almost uncountably more money than science agencies probably doesn’t hurt either). But some researchers, of course, beg off. “There are obviously people who don’t want to do work with the DOD, and that’s fine,” Dunnicliff says.

RadiantNano’s founders wanted to work on this national-security side, and NSIN’s Propel is smoothing that path. The co-founders recently attended a demo day, where they showed off their tech and pitched potential funders, met startup accelerators, and hung out with DOD hotshots. They also have regular meetings with Propel partners to figure out how to get inside the proverbial and literal Pentagon. “Having a guide through that process—this, at times sometimes, byzantine process was really, really helpful for us,” says Dewan, RadiantNano’s co-founder and CEO. 

An X-ray image, in a way, of how things work on the inside.

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