DIELECTRIC-PROPERTIES OF THE QUASI-2-DIMENSIONAL ELECTRON LIQUID IN HETEROJUNCTIONS

A quasi-two-dimensional (Q2D) electron liquid (EL) is formed at the in terface of a semiconductor heterojunction. For an accurate characteriz ation of the Q2D EL, many-body effects need to be taken into account b eyond the random phase approximation. In this theoretical work, the se lf-consistent static local-field correction known as STLS is applied f or the analysis of the Q2D EL. The penetration of the charge distribut ion to the barrier-acting material is taken into consideration through a variational approach. The Coulomb form factor that describes the ef fective 2D interaction is rigorously treated. The longitudinal dielect ric function and the plasmon dispersion of the Q2D EL are presented fo r a wide range of electron and ionized acceptor densities choosing GaA s/AlxGa1-xAs as the physical system. Analytical expressions fitted to our results are also supplied to enable a widespread use of these resu lts.