title: Beam instabilities in the scale-free regime.
abstract: The instabilities arising in a one-dimensional beam sustained by the diffusive photorefractive nonlinearity in out-of-equilibrium ferroelectrics are theoretically and numerically investigated. In the "scale-free model," in striking contrast with the well-known spatial modulational instability, two different beam instabilities dominate: a defocusing and a fragmenting process. Both are independent of the beam power and are not associated with any specific periodic pattern.
authors.affiliation: Institute for Complex Systems-CNR, Department of Physics, University Sapienza, Piazzale Aldo Moro 2, 00185 Rome, Italy.
authors.forename: V
authors.initials: V
authors.lastname: Folli
authors.forename: E
authors.initials: E
authors.lastname: DelRe
authors.forename: C
authors.initials: C
authors.lastname: Conti
mesh_terms: D003198:Computer Simulation; D008962:Models, Theoretical; D055620:Optical Phenomena