New approach for detection and identification of substances using THz TDS

摘要

We propose and discuss new effective approach for the detection and identification of substances using a THz TDS. It consists in using a substance emission at high frequencies corresponding to high energy levels relaxation due to cascade mechanism of their excitation under the broadband THz pulse action. The second approach is based on a possibility of observing the absorption frequencies of substance under the frequency up-conversion. To explain a physical mechanism of considered possibilities we make a computer simulation using ID Maxwell's equations and density matrix formalism.