Description

Terahertz radiation, sometimes referred to as submillimeter radiation, terahertz waves, extraordinarily high frequency (THF), T-rays, T-waves, T-light, T-lux, or THz, is a category of electromagnetic waves having frequencies between 0.3 and 3 terahertz that have been defined by the International Telecommunication Union. Radiation in the terahertz frequency has wavelengths between 1 mm and 0.1 mm. Specifically, in astronomy, terahertz radiation is frequently referred to as the submillimeter band and its radiation as submillimeter waves since it starts at a wavelength of one millimetre and progresses into shorter wavelengths. Information about terahertz science, terahertz photodetectors, and terahertz lasers is included in the book. A particular focus is placed on long wavelength photodetectors based on innovative quantum dots operating at ambient temperature. The book concludes with a discussion of multi-color laser concepts for the terahertz spectrum. It is written as background information for graduate students studying optics.