An attosecond ionization gating is achieved using a few-cycle laser pulse in combination with its second harmonic. With this gating, the generation of the electron wave packet (EWP) is coherently controlled, and an isolated EWP of about $270\mathrm{as}$ is generated. An isolated broadband attosecond extreme ultraviolet pulse with a bandwidth of about $75\mathrm{eV}$ can also be generated using this gating, which can be used for EWP measurements as efficiently as a $50$-as pulse, allowing one to measure a wide range of ultrafast dynamics not normally accessible before.

• Received 26 March 2007

DOI:https://doi.org/10.1103/PhysRevA.76.051801