2020/01/17 by Y. X. Zhang, S. Rykovanov, Mingyuan Shi +4
Physics and Astronomy · #physics.plasm-ph #physics.optics
paper · pdf · doi:10.1103/physrevlett.124.114802
arxiv created 2020/01/17 · arxiv updated 2020/04/22
A new regime in the interaction of a two-colour (ω,2ω) laser with a nanometre-scale foil is identified, resulting in the emission of extremely intense, isolated attosecond pulses - even in the case of multi-cycle lasers. For foils irradiated by lasers exceeding the blow-out field strength (i.e. capable of fully separating electrons from the ion background), the addition of a second harmonic field results in the stabilization of the foil up to the blow-out intensity. This is then followed by a sharp transition to transparency that essentially occurs in a single optical cycle. During the transition cycle, a dense, nanometre-scale electron bunch is accelerated to relativistic velocities and emits a single, strong attosecond pulse with a peak intensity approaching that of the laser field.