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SYNO: Nichtlineare und transversale Optik

SYNO II: HV II

SYNO II.1: Invited Talk

Monday, March 24, 2003, 14:30–15:00, F142

Controlling chaos and spatial disorder in lasers and nonlinear optical systems — •G.-L. Oppo — Department of Physics, University of Strathclyde, Glasgow, Scotland, U.K.

We review the most used techniques to control chaos and spatial disorder in nonlinear optical systems. We first present simple methods for the stabilisation of steady and periodic output during temporally chaotic evolution. We then extend these ideas to the spatio-temporal dynamics of broad area lasers and optical devices. Here, the coupling of diffraction with optical nonlinearities often leads to stationary or dynamical, regular or irregular, spatial structures. We describe the control of these spatio-temporal structures by means of effective perturbations leading to the stabilisation, selection and tracking of unstable spatial states of a pattern forming optical system. These techniques are based on small control signals obtained in the Fourier plane and have been successfully applied in a variety of experimental configurations in nonlinear optics. Control of defects and localised structures will also be discussed.