Novel phase-locked acceleration of a relativistic isolated attosecond electron sheet was realized using a relativistic reflected spatiotemporal optical vortex (STOV) pulse in three-dimensional particle-in-cell simulations. Electrons can be trapped in spatiotemporal phase singularity within the STOV pulse center, modulated into a ~600-as duration sheet, and phase-locked-accelerated to the GeV order in the longitudinal direction. Such an isolated attosecond electron sheet driven by the intense STOV pulse can be used in isolated attosecond pulse generation, ultrashort x/γ-ray radiation, and attosecond electron diffraction.

electron acceleration,ultraintense laser,Spatiotemporal laser