title: Bulk phonon scattering in perturbed quasi-3D multichannel crystallographic waveguide.
abstract: In the present paper, we concentrate on the influence of local defects on scattering properties of elastic waves in perturbed crystalline quasi-three-dimensional nanostructures in the harmonic approximation. Our model consists of three infinite atomic planes, assimilated into a perfect waveguide in which different distributions of scatterers (or defects) are inserted in the bulk. We have investigated phonon transmission and conductance for three bulk defect configurations. The numerical treatment of the problem, based on the Landauer approach, resorts to the matching method initially employed for the study of surface localized phonons and resonances. We present a detailed study of the defect-induced fluctuations in the transmission spectra. These fluctuations can be related to Fano resonances and Fabry-Pérot oscillations. The first is due to the coupling between localized defect states and the perfect waveguide propagating modes whereas the latter results from the interference between incidental and reflected waves. Numerical results reveal the intimate relation between transmission spectra and localized impurity states and provide a basis for the understanding of conductance spectroscopy experiments in disordered mesoscopic systems.
authors.affiliation: Laboratoire de Mécanique des Structures et Energétique, Département de Génie Mécanique, Faculté du Génie de la Construction, Université M. Mammeri, Tizi-Ouzou 15000, Algeria.
authors.forename: M S
authors.initials: MS
authors.lastname: Rabia