Unusual Size Dependence of Acoustic Properties in Layered Nanostructures

Abstract

Compared to symmetrically stacked layered structures, e.g., sandwich-like, much less is known about acoustic properties in a more general configuration lacking such a symmetry. Structures composed of layers with different characteristics (e.g., metal-insulator) are ubiquitous in nanotechnologies harnessing finite size and quantum effects. Explicit analytic expressions describing acoustic waves in a representative two-layer system are derived and analyzed in the full space of material parameters.