ultraviolet light, which measures as little as 135 nanometers, and infrared light, which can be as long as 1 millimeter, according materials compiled by NASA and Princeton University. (A millimeter is one thousandth of a meter.)
Many lasers are able to emit infrared waves with a wavelength of 750 nanometers to 3 microns, Marsland says. (A micron is one millionth of a meter, so a longer wave than a nanometer.) For example, lasers used in high-speed fiber-optic Internet networks and other communication protocols have wavelengths of around 1.55 microns, he says. But at wavelengths of around 3 microns and above, lasers become extremely inefficient, according to Botez.
“Beyond 3 microns—people cannot get those types of lasers to work,” he says.
Even so, that inefficient area is Intraband’s “sweet spot,” Marsland says. The area is called the middle infrared, and spans wavelengths of 3 to 10 microns, he says
Intraband is able to build lasers that operate in the middle infrared range because its devices use what is known as a quantum well—a part of quantum mechanics that layers thin semiconductors, sandwiching one type between two others in order to create a quantum effect on the electrons that create the laser. Adding extra barriers prevents electrons from passing through without a light-emitting energy transition, which would create inefficiencies at those longer wavelengths; that’s part of what has made reliable high power emission at 3 to 10 microns so elusive. The additional barriers are a key component of Intraband’s technology, Marsland says.
“This quantum well allows us to tune the energy levels to be just what we want them to be,” he says.
Organizations across many industries would benefit from lasers that emit light in that particular wavelength range, Marsland says. Engineers have been working on the science for decades, and it has applications in a range of industries, from medical devices to material processing to laser printing, according to a 2015 paper on quantum-well lasers. Intraband’s overarching goal is to make the laser more reliable and producible at high optical output powers, he says.
Marsland says that Intraband’s initial products will likely appeal most to an organization that’s interested in shooting a laser through the air and delivering power over a long distance. Companies that sell optical sensors might be among those that could benefit from using the startup’s devices, he adds. Two leaders in that industry are San Diego-based Daylight Solutions and Santa Clara, CA-based Picarro.
Intraband’s efforts to develop new laser technology have been supported by about $4 million in grant funding. The organizations that have backed either Intraband or its co-founders include the U.S. Department of Defense, Army, and Navy; the Wisconsin Alumni Research Foundation; and Northrop Grumman (NYSE: [[ticker:NOC]]), a large defense contractor.
Intraband has not raised any money from venture capital firms or angel investors, Marsland says.
By contrast, Alfalight, the company the UW-Madison engineers previously founded in 1998, reportedly raised more than $57 million in venture funding. However, Alfalight eventually ran into trouble selling to groups in the telecommunications field and others it targeted with its products. In 2013, Alfalight sold semiconductor manufacturing assets and product lines to Phoenix-based Compound Photonics for an undisclosed sum. Three years later, U.K.-based Gooch & Housego acquired Alfalight’s remaining assets for $1.3 million.
Marsland, who was not involved with Alfalight but is familiar with the trajectory of the business, says its fate “colors a lot of our decision-making” at Intraband.
“That’s one reason we’re being a little cautious on raising equity financing, and also about having our own fab,” he says. “It allows us to be more agile. We want to deliver quality products that our customers want, without being steered by the capital that’s been invested in us.”
Xconomy National Correspondent David Holley contributed to this report.
