The formation of moving kinks under the effect of collimated tubular optical beams

The dynamics of switching waves in optically bistable systems on the basis of growing absorption is analyzed by quasi-optical description. A new scena rio of kinks moving towards the optical beam under the action of a tubular optical beam is described. As opposed to an originally Caussian beam focuse d on to the entrance face, a high intensity at the exit from the medium und er the action of a collimated tubular beam is achieved due to the transform ation of its profile. The structures formed are shown to be identical for b oth cases of action. The scenario of the development of moving switching wa ves found in this work is an alternative to that known in the literature ea rlier, which developed under the action of Focused Gaussian beams and was a nalyzed with no regard for the variations of the phase of the optical beam. (C) 2000 MAIK "Nauka/Interperiodica".