Nowadays, techniques to detect Radiological and Nuclear (RN) agents are strongly requested in the field of homeland security (border and port security) and environmental security, for the rapid scanning of sensitive areas (restaurants, airports, subway stations, shopping malls, etc.) that are possible targets for terroristic threats like dirty bombs or silent sources. Thus, the development of smart radiation detectors that detect, measure, identify and analyse gamma ray emitting radioactive sources is a primary need.
IMEM has a decade of experience in radiation detectors, in particular CdZnTe (CZT) based systems. In respect to other radiation sensitive materials, CZT enables single photon counting (spectroscopic detection) and room temperature operation. Furthermore, thanks to its high stopping power, it is able to be sensitive to high energy radiation up to few MeV (i.e. in region of interest of gamma and cosmic radiation). For these reasons, CZT is the best candidate for the realization of light weight, robust and gamma-ray sensitive detectors which can be installed directly on Unmanned Aerial Vehicles (UAVs) for civil and military uses or on satellites for the deep space investigation.
Furthermore, the possibility to make spectroscopic detection of photons makes this material reliable for non-destructive tests like in-line scanner or imagers.
The detection of explosives is performed by revealing the vapours emitted by solid explosives. This requires devices with a sensitivity of the order of 1 molecules among 109 molecules of air.
This is done by means of functionalised nanostructures, based on carbon nanotubes (CNT) or semiconducting nanowires.