Optical absorption and sideband generation in quantum wells driven by a terahertz electric field

Linear optical absorption and terahertz sideband generation in quantum wells in the presence of a strong growth-direction oriented terahertz electric field is investigated. It is shown that the electric field not only produces multiple optical absorption peaks due to resonant coupling between the valence subbands—the Autler-Townes splittings—but also produces splittings in the generated sidebands. Due to the proximity of subbands in typical quantum wells, the terahertz field can couple more than two levels simultaneously and particular effects of that coupling are discussed.