R. Haupt

Electron-phonon interaction, dynamical screening and collective excitations in heterostructures: I. Electron-phonon interaction

Considering a GaAs-Ga1−xAlxAs heterostructure we investigate the single-particle Hamiltonian of the electron-(long-wave optical) phonon interaction. In detail the dispersion relations of long-wave optical phonons, i.e. of longitudinal optical (LO) phonons and of interface phonons of the polar semiconductor heterostructures are analyzed. The coupling function of the electron-phonon interaction is calculated using a continuum theory. The coupling functions describing the modified Frohlich interaction of a single electron with the continuous field of polarization of the LO and interface phonons are discussed and presented in graphical form.

Electron-phonon interaction, dynamical screening and collective excitations in heterostructures: III. Coupled intra- and intersubband plasmon-phonons

Abstract The complete spectrum of elementary excitations for the quasi two-dimensional electron gas interacting with the optical phonons of semiconductor heterostructures is calculated within the random-phase approximation. The dispersion curves of the coupled intra- and intersubband plasmon-phonons are plotted in graphical form for various cases. Considering the intersubband mixing we found that this yields only a very weak contribution to the dispersion curves of the plasmon-phonon modes. The theoretical results for the dispersion curve of the (0-0) intrasubband plasmons obtained, including exchange and correlation effects, coupling to the long-wavelength optical phonons, intersubband mixing and screening effects of the grating on top of the sample agree very well with experimental results from far-infrared transmission spectroscopy.

Electron-phonon interaction, dynamical screening and collective excitations in heterostructures. II, Dynamically screened potential

Abstract In this paper we analyze the dynamically screened interaction potential of a quasi two-dimensional electron gas of a heterostructure including the effects of the optical phonons. Using the subband structure of the electronic states, we calculate the bare and the screened interaction potential of two electrons interacting via electron-electron and electron-phonon interaction. The results are discussed and plotted in graphical forms.

Cyclotron resonance of magnetopolarons in anisotropic parabolic quantum dots

Abstract The interaction of electrons confined in a quasi-zero-dimensional anisotropic parabolic quantum dot and longitudinal-optical (LO) phonons, placed in a perpendicular magnetic field is calculated. Analytical and numerical results are presented for the anisotropy and polaron corrections to the Landau levels of an isotropic parabolic quantum dot.

Retardation effects on intra- and intersubband plasmons in quasi-one-dimensional quantum-well wires

Abstract The spectrum of the intra-and intersubband plasmon-polaritons of a quasi-one-dimensional quantum-well wire is investigated. The polarization tensor is treated in detail within the random-phase approximation. The dispersion curves of the collective excitations are calculated and presented in graphical form.