SEMICONDUCTOR SUPERLATTICES AS TERAHERTZ GENERATORS

Avoiding any truncation of the Hamiltonian for independent electrons in both ideal and imperfect superlattices subject to a uniform electric field, we show that dipole radiation in the terahertz range should be detectable for many members of the GaAs/AlxGa1-xAs system. The radition can be attributed to periodic Bloch oscillations in the case of ideal superlattices, and to almost-periodic oscillations, with the dominant frequencies on the order of the Bloch frequency, in the case of imperfect superlattices.