The terahertz (THz) spectral range has been under-utilized in the past both in fundamental research as well as in commercial applications. This spectral range is extremely important for studying condensed matter systems because the photon energy associated with THz frequencies is sub-meV, a typical energy for correlated electron physics; for instance this energy corresponds to the Cooper pair binding energy in superconductivity and the extremely important electron-electron interaction energy in doped semiconductors.
I will discuss experimental techniques that now allow scientists to study the electrodynamic response of systems in the THz range and present some of my research studying both magnetically and non magnetically doped semiconductors using the THz spectral range.