Conical wave propagation and diffraction in two-dimensional hexagonally packed granular lattices

Christopher Chong, Panayotis Kevrekidis, Mark Ablowitz, Yi-Ping Ma

Research output: Contribution to journalArticlepeer-review

9 Citations (Scopus)
22 Downloads (Pure)


Linear and nonlinear mechanisms for conical wave propagation in two-dimensional lattices are explored in the realm of phononic crystals. As a prototypical example, a statically compressed granular lattice of spherical particles arranged in a hexagonal packing configuration is analyzed. Upon identifying the dispersion relation of the underlying linear problem, the resulting diffraction properties are considered. Analysis both via a heuristic argument for the linear propagation of a wave packet and via asymptotic analysis leading to the derivation of a Dirac system suggests the occurrence of conical diffraction. This analysis is valid for strong precompression, i.e., near the linear regime. For weak precompression, conical wave propagation is still possible, but the resulting expanding circular wave front is of a nonoscillatory nature, resulting from the complex interplay among the discreteness, nonlinearity, and geometry of the packing. The transition between these two types of propagation is explored.
Original languageEnglish
Pages (from-to)012909
JournalPhysical Review E
Issue number1
Publication statusPublished - 25 Jan 2016


Dive into the research topics of 'Conical wave propagation and diffraction in two-dimensional hexagonally packed granular lattices'. Together they form a unique fingerprint.

Cite this