Phys.org June 3, 2019
Researchers in Germany working under the EU project CHEQUERS www.chequers.eu combined very fast widely tunable quantum cascade lasers with adjusted transmission and receiver optics, fast IR detectors and a fitting control and detection software. The miniaturized quantum cascade laser with an external resonator can scan the whole spectral range of the QC laser chip within just a millisecond. The measuring principle is based on selective spectral lighting of the target in the wavelength range of 1000—1300 cm-1. The chemical substance is identified based on the intensity of the backscattered light and the illumination wavelength. The spectral fingerprint is matched with the integrated database that contains a large amount of safety-relevant substances, and thus the substance can be identified. The device succeeded at a series of test measurements detecting many explosives and their precursor materials and has thus proven that the technology works…read more.
Credit: Fraunhofer Institute for Applied Solid State Physics IAF