Dynamic Franz-Keldysh effect on magnetoexcitons in quantum wells: beyond perturbation theory

We consider the optical properties of free electron-hole pairs and excitons in a quantum well in a strong THz-frequency electric field polarized in the quantum-well plane (linearly or circularly polarized) and a crossed static magnetic field in the growth direction. The interplay of the THz and magnetic fields leads to distinctive features in the optical spectra for a linearly polarized THz field, the optical spectra exhibit THz sidebands, while the sidebands are suppressed for circularly polarized fields. The optical spectra are also strongly suppressed-and in fact formally disappear in the absence of excitons-when the cyclotron and THz frequencies coincide. (C) 1999 Elsevier Science Ltd. All rights reserved.