EFFECT OF HALF-SPACE AND INTERFACE PHONONS ON THE TRANSPORT-PROPERTIES OF ALXGA1-XAS GAAS SINGLE HETEROSTRUCTURES/

We present a detailed analysis of the influence of the various phonon modes characteristic of the single heterostructure AlxGa1-xAs/GaAs on its electronic transport by using a Monte Carlo simulation. The electr onic states of the system are calculated by solving self-consistently the coupled Schrodinger-Poisson equations for the system. LO-phonon st ates are treated within the dielectric continuum model by using two di fferent dielectric functions to describe the two semiconductors, the u sual Lyddane-Sachs-Teller expression for GaAs and a generalized two po les expression for AlxGa1-xAs. Two sets of optical modes characterize the system, the half-space LO modes and the interface modes. The scatt ering rates for the interaction of these modes with the confined elect rons are calculated from the Fermi golden rule. A Monte Carlo simulati on is then used to study the effect of the electron-phonon interaction on the transport properties of a single AlxGa1-xAs/GaAs heterostructu re in the presence of an electric field applied along the heterointerf ace. The results of simulations performed at 300 and 77 K compare favo rably with available experimental data. Drag and heating effects relat ed to nonequilibrium phonon effects are found and discussed.