Some dynamic properties for a light ray suffering specular reflections inside a periodically corrugated waveguide are studied. The dynamics of the model is described in terms of a two dimensional nonlinear area preserving map. We show that the phase space is mixed in the sense that there are KAM islands surrounded by a large chaotic sea that is confined by two invariant spanning curves. We have used a connection with the Standard Mapping near a transition from local to global chaos and found the position of these two invariant spanning curves limiting the size of the chaotic sea as function of the control parameter.

We have studied a dissipative version of a one-dimensional Fermi accelerator model. The dynamics of the model is described in terms of a two-dimensional, nonlinear area-contracting map. The dissipation is introduced via inelastic collisions of the particle with the walls and we consider the dynamics in the regime of high dissipation. For such a regime, the model exhibits a route to chaos known as period doubling and we obtain a constant along the bifurcations so called the Feigenbaum's number delta.

Some dynamical properties for a simplified version of a one-dimensional Fermi Accelerator Model under the action of a small dissipation is studied. The dissipation is introduced via a damping force which is assumed to be proportional to the square particle's velocity. The dynamics of the model is described by using a two-dimensional, nonlinear area contracting mapping for the variables velocity of the particle and time. Our results confirm that the structure of the phase space of the conservative version is replaced by a large number of attracting periodic orbits. For a fixed set of control parameters, we obtain many periodic attractors and show that most of them posses low period. The stable orbits produce a complex structure of basin of attraction whose limit cover almost all phase space, thus suggesting a fractality.

The chaotic low energy region (chaotic sea) of the Fermi-Ulam accelerator model is discussed within a scaling framework near the integrable to non-integrable transition. Scaling results for the average quantities (velocity, roughness, energy etc.) of the simplified version of the model are reviewed and it is shown that, for small oscillation amplitude of the moving wall, they can be described by scaling functions with the same characteristic exponents. New numerical results for the complete model are presented. The chaotic sea is also characterized by its Lyapunov exponents.