NORMAL AND ANOMALOUS DIFFUSION IN A DETERMINISTIC AREA-PRESERVING MAP

Chaotic deterministic dynamics of a particle can give rise to diffusiv e Brownian motion. In this paper, we compute analytically the diffusio n coefficient for a particular two-dimensional stochastic layer induce d by the kicked Harper map. The variations of the transport coefficien t as a control parameter is varied are analyzed in terms of the underl ying classical trajectories with particular emphasis on the appearance and bifurcations of periodic orbits, When accelerator modes are prese nt, anomalous diffusion of the Levy type is observed. The exponent cha racterizing the anomalous diffusion is computed numerically and analyz ed as a function of the parameter. Copyright (C) 1998 Elsevier Science 1998 B.V.