Controlling on-off intermittent dynamics.

On-off intermittent chaotic behavior occurs in physical systems with symmetry. The phenomenon refers to the situation where one or more physical variables exhibit two distinct states in their time evolution. One is the ‘‘off’’ state where the physical variables remain constant, and the other is the ‘‘on’’ state where the variables temporarily burst out of the ‘‘off’’ state. We demonstrate that by using arbitrarily small feedback control to an accessible parameter or state of the system, the ‘‘on’’ state can be eliminated completely. This could be practically advantageous where the desirable operational state of the system is the ‘‘off’’ state. Relevant issues such as the influence of noise and the time required to achieve the control are addressed. It is found that the average transient time preceding the control obeys a scaling law that is qualitatively different from the algebraic scaling law which occurs when one controls chaos by stabilizing unstable periodic orbits embedded in a chaotic attractor. A theoretical argument is provided for the observed scaling law. @S1063-651X~96!05208-7#