Coupled Plasmon-phonon Modes in a Two-dimensional Electron Gas in the Presence of the Rashba Effect

Abstract

Elementary electronic excitation is studied theoretically for a two-dimensil electron gas in the presence of spin-orbit (SO) interaction induced by the Rashba effect. We find that in such a system, coupled plasmon-phonon excitation can be achieved via intra- and inter-SO electronic transitions. As a result, six branches of the coupled plasmon-phonon oscillations can be observed. The interesting features of these excitation modes are analysed.