The terahertz (THz) and sub-THz frequency region (100 GHz – 10 THz) of electromagnetic spectrum bridges the gap between microwaves and infrared. The “THz gap” is very attractive because of many possible applications in spectroscopy and imaging of biological objects, and in novel communication systems as well. THz Time Domain Spectroscopy
The typical THz-TDS setup is shown in Fig. 2. Subpicosecond pulses of THz radiation are detected after propagating through a sample and an identical length of a free space. A comparison of Fourier transforms of these pulse shapes gives the spectra of absorption and dispersion of the sample under investigation. Such measurements can be successfully performed for investigation of gases and organic materials.
