Wired:
Because it passes through clothes, terahertz radiation can
reveal hidden weapons and explosives. Unfortunately, water
vapor absorbs in the THz band, making it difficult to measure
reflected THz signals remotely. Now, Xicheng Zhang of
Rensselaer Polytechnic Institute and his colleagues have
developed a way of circumventing that limitation. In a paper
published on 11 July in
Nature Photonics
, they describe an ingenious method for what amounts to
converting the THz signal into a more penetrating UV
signal.
