Coupled plasmon–phonon modes in a two-dimensional electron gas in the presenceof the Rashba effect

Abstract

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