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.

• Received 31 July 2001

DOI:https://doi.org/10.1103/PhysRevE.65.017601