Spatial Structures and Temporal Dynamics in Photorefractive Nonlinear Systems
نویسنده
چکیده
This thesis deals with control of spatial structures and temporal dynamics in photorefractive nonlinear systems. The systems all utilize a photorefractive crystal as the key component, but produce structures of different spatiotemporal complexity. Four topics are experimentally examined: (1) the transfer of temporal fluctuations in photorefractive twoand three-beam coupling; (2) the spatial modes and their dynamics in a photorefractive ring oscillator with induced astigmatism; (3) the output characteristics of a single-mode laser diode array with frequency selective phase conjugate feedback; and (4) a minimally invasive method for control, manipulation, and stabilization of coexisting and underlying solutions in a pattern forming system. This thesis is submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Physics at the University of Copenhagen, Denmark. ISBN 87-550-2610-9 ISBN 87-550-2611-7 (internet) ISSN 0106-2840
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