Generation of attosecond electron packets in the interaction of ultraintense Laguerre – Gaussian laser beams with plasma

The interaction of a thin plasma foil with two counterpropagating circularly polarised Laguerre – Gaussian laser beams of ultra-high intensity is studied using pwarticle-in-cell simulations in a fully three-dimensional geometry. It is found that within the course of the interaction, bunched electron packets are generated from the plasma target. Each packet has a duration of about 830 attoseconds, and adjacent bunches are spatially separated by one laser wavelength. The emitted electron packets move at ultrarelativistic velocities along the axis of laser propagation.