Figure 3

Ion motion within the space charge field created by the laser pulse. (a) Snapshot of the electron density profile (grey color scale), superimposed with the transverse velocity distribution of \({He}^{2+}\) (red–white–blue color scale) at time \(940.45{/\omega }_{0}\). (b) Transverse field distribution along the x directions at z = \(990c{/\omega }_{0}\) at various times. The propagation direction of the laser pulse is from left to right. The central axis of the laser pulse is located at \(x = 500c/{\omega }_{0}\).