Skipping Orbit Electron Motion in GaAs-AlGaAs Quantum Wires Detected by Raman Spectroscopy

Abstract

We have investigated the elementary electronic excitations of the quasi-one-dimensional (1D) magnetoplasma in GaAs-AlGaAs quantum wires by resonant inelastic light scattering. In narrow quantum wire samples we observe the 1D intrasubband plasmon if a wave vector is transferred parallel to the wire direction. This 1D plasmon shows a negative dispersion with magnetic field, which arises from skipping orbit motion of the individual electrons at the edges of the wires. We find evidence for a coupling between adjacent wires in these samples with relatively small periods. Furthermore, we demonstrate theoretically and experimentally that in Raman experiments on confined magnetoplasmons in quantum wire structures with parabolic confinement the generalized Kohn theorem can be broken by using wave vector transfers q > 0.