Pattern formation and competition in photorefractive oscillators
Anno: 1994
Autori: Arecchi F.T., Boccaletti S., Puccioni GP., Ramazza PL., Residori S.
Affiliazione autori: Istituto Nazionale di Ottica, Largo E. Fermi 6, 50125 Firenze, Italy
Abstract: We introduce a general model of pattern formation in optical systems made of a cavity with an active medium as a photorefractive crystal fed by a pump. The model is based on the interplay of a diffractive equation for the optical field and a diffusive equation for the medium refractivity. The aim of the model is to describe a series of experiments which have shown mode competition (periodic or chaotic alternation) for low Fresnel numbers (F) and mode coexistence, leading to short range space correlations, for high F. For low F, a linear stability analysis provides the set of modes above threshold as a function of the transverse wave number. Due to the interplay of the optical and the diffusive interactions, different behaviors result depending on the thickness of the medium as compared to the optical absorption length and diffusion length. Including the leading nonlinearities compatible with the symmetry constraints, we introduce normal form equations which describe the time-dependent mode competition. In the case of a large number of modes (high F), nonlinear mode-mode interaction is equivalent to a self-induced noise. In this limit, the relevant feature to be compared with the experiment is the power spectrum.
Giornale/Rivista: CHAOS
Volume: 4 (3) Da Pagina: 491 A: 498
Maggiori informazioni: Work partly supported by EEC-Esprit Basic Research action TONICS (Contract No. 7118).DOI: 10.1063/1.166027Citazioni: 8dati da “WEB OF SCIENCE” (of Thomson Reuters) aggiornati al: 2024-05-12Riferimenti tratti da Isi Web of Knowledge: (solo abbonati) Link per visualizzare la scheda su IsiWeb: Clicca quiLink per visualizzare la citazioni su IsiWeb: Clicca qui