Quantum modifications of classical diffusion in coordinate space for chaotic systems

Abstract
The paper considers the dynamics of a particle in a periodically- spaceand t approach the distribution function for the particle position is shown to obey a diffusion law. We study the process of diffusion in the quantum case. It is found that quantum interference effects cause an acceleration of diffusion. A charged particle in a standing-wave field is shown to be a physical system where the discussed phenomenon might be observed.