Inelastic Light Scattering of Electronic Excitations in Quantum Wells

Abstract

Raman scattering has been used extensively to study various aspects of electronic excitations in low dimensional semiconductor structures. Shortly after the first proposal by Burstein et al.¹ which was based on resonant electronic light scattering experiments in n-type bulk GaAs², the first observations of intersubband transitions in GaAs/Al_xGa_1-xAs heterojunctions³ and quantum wells⁴ were reported. It became clear very soon that this technique offers the unique possibility to separate single particle and collective electronic excitations in two-dimensional electron systems. Numerous publications appeared since then for many semiconductor structures under different conditions. These include also plasmon excitations in low-dimensional systems^5,6. An overview of the various aspects is given in the recent articles in Topics in Applied Physics IV and V⁸, and in the proceedings of a related NATO workshop held at Mont Tremblant in 1990⁹. For more details the interested reader is refered to these review articles and the original references given therein.