Quantum diffusion in a biased kicked Harper system, modeling field-induced transport in superlattices, is studied for fully chaotic dynamics of the underlying classical system. Under these conditions, the classical transport is diffusive whereas the quantum diffusion can be either enhanced or suppressed for commensurable or incommensurable ratio of the Bloch period to the driving period, respectively. The quantum transport properties are related to the statistical properties of the quasienergy spectra as described by random matrix theory.

• Received 16 May 2003

DOI:https://doi.org/10.1103/PhysRevE.68.046202