Physical Phenomena in Electronic Materials in the Terahertz Region

Terahertz radiation is a powerful probe of materials´ properties, because many materials have characteristic energies corresponding to the energies of terahertz photons. Take the particular example of semiconductor materials: phonon energies, cyclotron energies, and the energy levels of bound states in quantum wells, all typically lie in the terahertz region. Contrariwise, the properties of materials are crucial in the development of terahertz technology. This applies to every part of the system-from emitter, through elements for transferring and manipulating the radiation, and finally to the detector.