Granular crystals: Nonlinear dynamics meets materials engineering

Granular crystals: Nonlinear dynamics meets materials engineering

Nonlinear waves in granular crystals

We investigate excitations in one-dimensional granular crystals, i.e. chains of solid beads with nonlinear interaction forces. These chains have attracted attention because of their relative experimental simplicity and interesting dynamics. They can be modelled as chains of coupled oscillators in a model reminiscent of the celebrated Fermi-Pasta-Ulam (FPU) equations. The nonlinearity of the int...

Nonlinear Waves in Granular Crystals

The properties and stabilities of various wave types are investigated in nonlinear lattices with a ‘Hertz’ type potential. In particular the interaction of intrinsic localized modes with other waves is studied. Evidence is provided that Fano-like resonances, observed in other nonlinear systems, cannot occur in Hertzian lattices.

Dynamics of levitated granular materials

Engineering two-dimensional nonlinear photonic quasi-crystals.

A known algorithm for modeling quasi-periodic lattices is used to generate two-dimensional quadratic nonlinear photonic quasi-crystals containing a set of desired discrete spectral components. This allows us to fabricate optical devices in which an arbitrary set of nonlinear optical processes can be efficient. We demonstrate this capability by fabricating two devices: a multidirectional single-...