| Popis: |
Chapter 10 which covers manipulation and control of self-organized patterns by spatio-temporal techniques, the desire of researchers in this field to adjust and stabilize defined pattern states instead of passively observing spontaneous pattern formation is approached. An additional system parameter, a frequency detuning of the pump beams, is introduced and allows us to choose a particular pattern state when two or more patterns are accessible for one given set of parameters. The unique real-time access to the spatial frequency domain that is available in optics is exploited for the realization of a spatial control scheme based on the manipulation of wave numbers in the Fourier plane. Direct filtering in the feedback arm is shown to be an excellent tool for forcing the system to a desired solution. The feedback system and, thereby, its solutions are changed by any intervention in the system, which motivates us to consider an extension of this invasive scheme. |
