Laser frequency combs may help detect chemical warfare agents in the air
Dual mid-IR frequency combs will rapidly detect airborne substances in a massively parallel way.
A mid-IR spectroscopic approach developed by Konstantin Vodopyanov, a professor at the University of Central Florida (UCF; Orlando, FL) College of Optics and Photonics (CREOL), can potentially sense chemical or biological warfare agents in the atmosphere swifty and accurately -- swiftly, as it can simultaneously acquire 350,000 spectral data points; and accurately, as it senses with part-per-billion sensitivity and sub-Doppler resolution.1
The light source is two optical parametric oscillators (OPOs) pumped by two phase-locked thulium-fiber frequency combs; as a result, a 3.1 to 5.5 µm spectral range is covered at 150 MHz intervals. The comb-tooth linewidths are a minuscule 25 mHz.
With such sensitivy and range, even if someone tried to hide toxic chemicals, this technique could be able to detect them.
"We still have much work ahead," says Vodopyanov. "We are now working on broadening the range of the laser frequencies that can get the job done. If costs can be reduced and the tech made mobile, the applications could be endless."
A similar principle is used in the medical field to detect biomarkers for different kinds of health conditions, including cancer, by taking breath samples.
The novel approach could open the door for developing noninvasive technology, including sensors, that could be used to detect:
--airborne agents that could be encountered in a biological or chemical attack at home or on the battlefield
--traces of life by missions to other planets or asteroids
Other collaborators on the Nature Photonics paper include Andrey Muraviev at CREOL, Viktor Smolski of IPG Photonics -– Mid-Infrared Lasers (Birmingham, AL), and Zachary Loparo from UCF’s Department of Mechanical and Aerospace Engineering.
1. A. V. Muraviev1 et al., Nature Photonics (2018); doi:10.1038/s41566-018-0135-2.