SKIPPING ORBIT ELECTRON MOTION IN GAAS-ALGAAS QUANTUM WIRES DETECTED BY RAMAN-SPECTROSCOPY

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