Effects of an external electric field on one-phonon resonant and electron Raman scattering in a semiconductor quantum wire

Abstract

In this work, the influence of an external electric field is studied in two cases: one-phonon resonant Raman scattering and one-phonon electron Raman scattering, processes that occur in a semiconductor quantum wire with cylindrical symmetry and finite potential barriers. Where we have considered that the electric field is homogeneous and transversal to the system axis. To carry out this study, we obtain a mathematical expression for the differential cross-section for both Raman processes, where for one-phonon resonant Raman scattering, intra-band and inter-band optical transitions are considered, while for one-phonon electron Raman scattering, only intra-band optical transitions are considered. Therefore, to determine the electronic states, we use a valid model when the electric field is weak with respect to confinement. In the case of the Fröhlich electron–phonon interaction, we use a model in which the oscillation modes are completely confined, a model that was developed within the framework of a macroscopic continuum model. Then, the singularities present in the Raman spectra and the effect of the electric field on their position and intensity are analyzed. Finally, how the electric field affects the electron–phonon interaction and the selection rules for optical transitions in a semiconductor quantum wire with cylindrical symmetry are shown.