Recent progress of THz spectroscopy in the detection of explosives

The newly developed technique of THz spectroscopy has made much progress in aviation, life science and safety inspection. Many explosives have characteristic absorptions in the THz region, and non－metallic and non－polar materials are transparent to THz waves. In addition, THz radiation has low photon energies and does not cause photon ionization so it has great potential in safety inspection. This paper reviews the status quo of THz spectroscopy of explosives, including our investigations. The hurdles and challenges of THz technology in safety inspection are discussed.