Imagine this disaster scenario: A pipe bursts in an industrial facility, spraying a cloud of tiny droplets into the air. But the workers were lucky. Within minutes, a laser device the size of a small suitcase detects the cloud and tells security services what’s inside so they know how to respond.

That’s the vision of a new project from a team of engineers and chemists from the University of Colorado at Boulder, the Cal Institute of Technology, the University of California, Santa Barbara, and three companies. It is funded through a new contract with Intelligence Advanced Research Activities (IARPA), part of the federal Office of the Director of National Intelligence.

This effort, named Standoff Aerosol Measurement Remote Optical Network (SAURON), takes its name from a villain in the Lord of the Rings book series; This villain is a being who usually takes the form of a burning eye and whose “gaze pierces clouds, shadows.” , World.”

“The idea is an all-seeing eye that can detect hazardous aerosols in the midst of many other substances,” said Greg Ricker, the Paul M. Ready Professor of Mechanical Engineering and principal investigator of the project.

He explained that SAURON will focus on aerosols, the term used for a wide variety of small particles floating in the air. Some aerosols may contain chemicals that pose a serious hazard to humans, such as polycyclic aromatic hydrocarbons. Ammonium nitrate, a substance commonly used in explosives, also creates aerosols. So can fentanyl, an opioid drug that can be fatal even in small amounts.

To detect such dangers, the team turns to a Nobel Prize-winning technology called frequency comb laser. The researchers hope that their device will help protect people in the near future from a variety of airborne threats, including industrial accidents and even possible chemical attacks in crowded cities.

“The lasers will be battery-powered, so you can place them in an airport, city blocks or industrial facilities where hazardous materials are used,” said Scott Diddams, a professor in the Department of Electrical, Computer and Energy Engineering. “From the very beginning, people will know if there is a malfunction or a leak.”

The project’s co-investigators from CU Boulder are Diddams, Daven Genze, professor of mechanical engineering, and Jose Jimenez, professor of chemistry and member of the Cooperative Research Institute for Environmental Sciences (CIRES).

To see the invisible

Detection of hazardous aerosols is in many respects the main task of the “needle in the haystack”. The air people breathe is much more complex than it seems.

“At any given time, methane, carbon dioxide and other samples of what we call volatile organic compounds are present in the atmosphere,” Ricker said. “A lot of confusion.”

The team believes frequency-comb lasers could help overcome this confusion.

Diddams was one of the team members at JILA, a joint research institute between CU Boulder and the National Institute of Standards and Technology (JILA), that pioneered these tools. The group, led by Nobel laureate Ian Hall, used frequency comb lasers for research in quantum metrology and optical clocks. Unlike traditional lasers, frequency comb lasers emit a beam of light with millions of colors simultaneously.

If you shift this light across the environment, these lasers can act like an aerosol fingerprint scanner, detecting signals from even very small concentrations of particles or gases in the air. The project team includes LongPath Technologies, which uses these tools to find methane leaks at oil and gas facilities. Ricker co-founded LongPath in 2017.

For three and a half years, SAURON researchers will work to make their laser more precise and compact. To do this, the group is applying a new “integrated photonics” technology pioneered by Kerry Wahala of the Caltech Institute, John Bowers of the University of California, Santa Barbara, and the companies Nexus Photonics and hQphotonics. The team will develop their devices on small microcircuits that transmit information with light beams, not electronic signals. The work is part of the Quantum Engineering Initiative at CU Boulder.

“They are similar to traditional silicon computer chips, but light is generated, transported and interacted in ways that are useful for perception,” Diddams said.

SAURON is an example of how researchers at CU Boulder are turning advances in basic science into tangible technologies that could one day protect people.

“We are taking technologies developed for quantum science and translating them into a wide range of applications,” Ricker said.