When dielectric spectroscopy meets THz spectroscopy; the tale of two estranged brothers

The study of dielectric properties of biological systems and their components is important not only for the fundamental scientific knowledge but also for its applications in medicine, biology, and biotechnology. The technique - known as dielectric spectroscopy (DS) - received impetus from the advent of impedance and network vector analyzers in late nineteen eighties. This new technology made it possible for researchers quickly and accurately to acquire time- or frequency-spectra of permittivity and conductivity in an extremely wide frequency band (10-6-1012Hz). The link between well-developed traditional DS and the recently appeared THz spectroscopy will be briefly reviewed in the paper.