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Secondary bifurcations of hexagonal patterns in a nonlinear optical system: alkali metal vapor in a single-mirror
Damià Gomila1, Thorsten Ackemann, Edgar Grosse Westhoff
1Institut Mediterrani d'Estudis Avançats, IMEDEA (CSIC-UIB), Campus Universitat Illes Balears, E-07071 Palma de Mallorca, Spain.
Abstract:
Secondary bifurcations of hexagonal patterns are analyzed in a model of a single-mirror arrangement with an alkali metal vapor as the nonlinear medium. A stability analysis of the hexagonal structures is performed numerically. Different instabilities are predicted in dependency on the wave number of the hexagons. Some of the instabilities take place at a finite wave number and result in the formation of structures with 12 spatial modes. These structures are compared with those observed experimentally.
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