DYNAMICS OF CHAOS-ORDER INTERFACE IN COUPLED MAP LATTICES

We study a coupled map lattice model with two states: a simple fixed p oint and spatio-temporal chaos. Preparing properly initial conditions, we investigate the dynamics of the interface between order and chaos. In the one-dimensional lattice regimes of irregular and regular front propagation behavior are observed and analyzed by introducing a local front map and a front Lyapunov exponent. Corresponding to these diffe rent regimes of front propagation we can characterize different types of transitions from laminar state to chaos using comoving Lyapunov exp onents. In the two-dimensional lattice these types of front motion are related to regimes of roughening and flattening of the interface.