Benjamin Clough, doctoral student at the Rensselaer Polytechnic Institute, has been awarded the 2011 Lemelson-MIT Rensselaer student prize.
The $30,000 award was given to Clough for developing an innovative technology, which allows for remote detection of hidden chemicals, explosives and other harmful materials.
Moisture in air is known to weaken terahertz waves and the limited effectiveness makes its application in bomb detection impractical. The cost-effective method devised by Clough uses sound waves to amplify the effectiveness of terahertz spectroscopy from a distance of few feet to quite a few meters.
Clough’s project, titled Terahertz Enhanced Acoustics, involved the use of 2 laser beams, which produces bursts of plasma when focused in air. This in turn creates terahertz pulses. A second pair of lasers focused close to the target produces new plasma capable of detecting terahertz pulses after interaction with the source. A sensitive microphone detects the terahertz wave data present in the acoustic wave produced by the second plasma. The detected audio data upon conversion into digital data can be verified quickly against a library of terahertz fingerprints to find out the unknown material’s chemical composition.
The patent-pending method can be applied in monitoring smokestack emissions, environmental monitoring of atmospheric conditions, detecting land mines or inspecting suspicious packages without potential risk to the user.