Phonon resonances in optical spectra of donors in quantum wells

An influence of electron-phonon coupling and electron confinement on optica l spectra is studied for donors in semiconductor quantum wells. A binding a nd 1s-2p transition energies have been calculated by the optimized canonica l transformation method for GaAs/AlGaAs, CdTe/CdZnTe, and CdF2/CaF2 quantum wells. We have found that - in the quantum wells made from the ionic semic onductors - the 1s-2p transition energy exceeds the LO-phonon energy and th e phonon resonances can appear in the optical spectra of donors. We have es timated the parameters of quantum wells, for which the phonon resonances ca n be detected in the absence of external magnetic field. (C) 1999 Elsevier Science B.V. All rights reserved.