250-nm narrow quantum wires have been prepared by deep-mesa etching of modulation-doped GaxIn1-xAs heterostructures. The far-infrared response of these quantum wires is strongly governed by collective excitations. In tilted magnetic fields B we observe a resonant coupling of these collective wire modes to two-dimensional 2D) energy states, i.e., states that arise from the confinement in the original 2D system. We can qualitatively explain this coupling, in particular the observed anisotropy with respect to the tilt directions, within a one-particle model. Quantitatively, however, the coupling appears drastically enhanced in the 1D quantum wires as compared to the coupling in 2D systems.
ASJC Scopus subject areas
- Condensed Matter Physics