The interaction of light with matter is the basis of spectroscopy, a set of techniques lying at the heart of physics and chemistry. From infrared light to X-rays, a broad sweep of wavelengths is used to stimulate vibrations, electron transitions, and other processes, thus probing the world of atoms and molecules. However, one lesser-used form of light is the terahertz (THz) region. Lying on the electromagnetic spectrum between infrared and microwaves, THz radiation does have the right freque...
