Transport in time-dependent random potentials

The classical dynamics in potentials that are random both in space and time is studied. The potentials are generated by a stationary process. This can be intuitively understood with the help of Chirikov resonances that are central in the theory of chaos, and explored quantitatively in the framework of the Fokker-Planck equation. In particular, a simple expression for the diffusion coefficient was obtained in terms of the average power density of the potential. The resulting anomalous diffusion in velocity is classified into universality classes. The general theory was applied and numerically tested for specific examples relevant for optics and atom optics.