Scientists develop technique to identify explosives and dangerous gases by remotely using lasers

A product based on the system can be used at airports, toll booths, environmental monitoring of pollutants, and in the battlefield. Researchers from the University of Michigan have combined two existing techniques to remotely and rapidly identify explosives and dangerous gases. The multi-dimensional coherent spectroscopy technique allows researchers to identify gases from a distance by looking at the portions of the spectrum absorbed by the gases, which acts like a signature for the gases. The researchers used two frequency combs to tell the difference between two rubidium isotopes, a difference that could not be measured using the conventional MCDS technique. Future plans for the project include adding a third frequency comb, as well as use laser-based fibre optics that would allow the identifications of more chemicals by looking at them further into infrared light.