Phonons in quantum wires

The authors present a detailed study of phonons in rectangular quantum wires within the dielectric continuum model and within a fully microscopic approach. From the latter, they calculate the phonon dispersions and the potentials associated to the individual modes. The classification of such modes is much more complex than in the corresponding two dimensional case, owing to the intrinsic coupling of confined and interface modes associated to both directions perpendicular to the wire. This indicates a failure of the current implementations of the macroscopic dielectric continuum model