Power (or energy) detectors
Detectors of terahertz electromagnetic radiations

In a bolometer, the incident THz beam is absorbed and heats a material. The electrical resistivity of this material, or of a material adjacent to the absorbing material, depends on temperature. The absorbed THz power P_THz, which increases the temperature T of the material, is determined by measuring the change in resistance R of the material, i.e. by simply applying a voltage V to the material and reading the value of the electric current flowing through it (figure...