Cascaded generation of isolated sub-10 attosecond half-cycle pulses

Abstract Sub-10 attosecond pulses (APs) with half-cycle electric fields provide exceptional options to detect and manipulate electrons in the atomic timescale. However, availability of such is still challenging. Here, we propose a method generate isolated sub-10 based on cascade process naturally happening plasma. A backward AP first generated by shooting moderate overdense plasma one-cycle femtosecond pulse. After that, an electron sheet thickness several nanometers formed accelerated forward electrostatic field. Then this goes through unipolar perturbations driven tail first-stage instead initial laser As result, cascadedly produced transmission direction. Two-dimensional particle-in-cell simulations indicate that pulse duration 7.3 attoseconds can be from cascaded scheme. Apart driving pulse, scheme also realized commercial 100 TW 25 fs shaping relativistic lens advance.