  We explore the prospects to control by use of time-dependent fields quantum
transport phenomena in nanoscale systems. In particular, we study for driven
conductors the electron current and its noise properties. We review recent
corresponding theoretical descriptions which are based on Floquet theory.
Alternative approaches, as well as various limiting approximation schemes are
investigated and compared. The general theory is subsequently applied to
different representative nanoscale devices, like the non-adiabatic pumps,
molecular gates, molecular quantum ratchets, and molecular transistors.
Potential applications range from molecular wires under the influence of strong
laser fields to microwave-irradiated quantum dots.
