TERAHERTZ WAVE EMITTING ELEMENT AND TERAHERTZ WAVE EMITTING DEVICE

摘要

A terahertz wave emitting element includes a semiconductor chip (11) to which a first impurity is added and a light source (10) for irradiating the semiconductor chip (11) with light. The activation energy of the added first impurity at room temperatures brings about an impurity level corresponding to the light energy of a terahertz wave. The impurity levels include an exited level which is empty because of the position of the Fermi level. The light energy of the light shone at the semiconductor chip (11) is above the band gap energy of the semiconductor chip (11) at room temperatures. The semiconductor chip (11) is optically pumped by means of the light source (10) at room temperatures. Electrons, which are optically excited carriers, in the conductive band of the semiconductor chip (11) and holes in the valence band recombine because of the band-to-band transition of the semiconductor chips (11) via the impurity level including an empty excited level, and thereby a terahertz wave is emitted.