Theory of acoustic band structure of periodic elastic composites

We study an elastic composite described by the position-dependent mass density \ensuremath{\rho}(r), the longitudinal speed of sound ${\mathit{c}}_{\mathit{l}}$(r), and the transverse speed of sound ${\mathit{c}}_{\mathit{t}}$(r). For a spatially periodic composite---a ``phononic crystal''---we deri... View More