Attosecond physics

Experiments on the sub-femtosecond time scale performed in recent years and their theoretical background are reviewed in this article. We present the essentials of the generation of attosecond pulses, phase-stabilized few-cycle laser pulses, and applications to sub-femtosecond control of electronic motion and time-resolved spectroscopy of atoms and molecules. An outlook on emerging pulse-generation techniques and time-resolved imaging of electronic and molecular structure is included.