Influence of time delayed global feedback on pattern formation in oscillatory CO oxidation on Pt(1 1 0)

Spatiotemporal pattern formation in the catalytic CO oxidation on Pt(1 1 0) is controlled by means of global delayed feedback applied through the gas phase. Using photoemission electron microscopy we have investigated the dynamical response of the system to a change of feedback intensity and time delay. Well defined synchronization and desynchronization regimes alternate when the delay is varied. In the case of synchronization the surface shows spatial homogeneous oscillations whereas in the case of desynchronization non-uniform patterns are observed. Furthermore two-phase clusters with period doubled local oscillations are studied. Phase balance between single cluster areas and breathing cluster modes are observed.