Controlling Chemical Turbulence by Global Delayed Feedback: Pattern Formation in Catalytic CO Oxidation on Pt(110)
Minseok Kim,
Matthias Bertram,
Michael Pollmann,
Alexander von Oertzen,
Alexander S. Mikhailov,
Harm Hinrich Rotermund,*
Gerhard Ertl
Control of spatiotemporal chaos is one of the central
problems of nonlinear dynamics. We report on suppression of chemical turbulence by global delayed feedback using, as an example, catalytic carbon monoxide oxidation on a platinum (110) single-crystal surface and carbon monoxide partial pressure as the controlled feedback variable. When feedback intensity was increased, spiral-wave turbulence was transformed into new intermittent chaotic regimes with cascades of
reproducing and annihilating local structures on the background of
uniform oscillations. The global feedback further led to the development of cluster patterns and standing waves and to the stabilization of uniform oscillations. These findings are reproduced by
theoretical simulations.
Abteilung Physikalische Chemie, Fritz-Haber-Institut der
Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
*
To whom correspondence should be addressed. E-mail:
rotermun{at}fhi-berlin.mpg.de