Eliminating spatiotemporal chaos and spiral waves by weak spatial perturbations

The possibility of eliminating spatiotemporal chaos and spiral waves by weak spatial perturbations in a spatially extended dynamical system is demonstrated numerically through the example of a wide-aperture laser. The time-independent weak spatial perturbation can effectively migrate the system from the state of spatiotemporal chaos or spiral waves to that of traveling waves. The threshold and the controllable range of the control parameters are given. By varying the amplitude or the spatial wave vector of the perturbation, drastic changes in the spatiotemporal dynamics are found.