title: Spontaneous nucleation of localized peaks in a multistable nonlinear system.
abstract: In a nonlinear optical experiment we report a unique class of localized structures, which appears as localized peaks of a pattern nucleating over another pattern. We show that this occurs when the system is driven through three pattern branches of solutions, accompanied by the appearance of localized peaks with two different amplitudes. Spontaneous creation and motion of localized peaks are triggered by amplitude and phase fluctuations of the underlying pattern. The scenario is universal and applies whenever a subcritical bifurcation exists between two different pattern solutions.
authors.affiliation: Institut Non-Linéaire de Nice, 1361 Route des Lucioles, 06560 Valbonne, France.
authors.forename: Umberto
authors.initials: U
authors.lastname: Bortolozzo
authors.forename: René
authors.initials: R
authors.lastname: Rojas
authors.forename: Stefania
authors.initials: S
authors.lastname: Residori