Shape profile of compactlike discrete breathers in nonlinear dispersive lattice systems

Abstract

We study the spatial decay profile of compactlike discrete breathers in nonlinear dispersive lattices. We show that the core region of such nonlinear localized excitations can be described by a cosinelike spatial shape while the tail region decays with a faster than exponential law, such as a superexponential one. We discuss the relation of the tail decay to properties of space-time separability.