Interface phonons of quantum wires.

We have used the continuum dielectric approach to study the optical-interface-phonon modes of a quantum-wire structure consisting of one material buried within another. Wires with a number of cross-sectional shapes have been studied. Analytical results are presented for wires with elliptical cross sections, of which the circular cross section is a special case. Numerical results using an integral-equation approach are given for wires with arbitrary cross-sectional shapes including rectangles having rounded corners. The dependence of the modes on the wire cross sections and their relation to the vibrational modes of planar quantum wells are discussed