Fig. 3: Coherent manipulation of ionic population by subcycle ionization injection.

a Dynamic evolution of electronic state populations of N\({}_{2}^{+}\) when the molecular axis is parallel to the laser polarization. b Variation of B(v = 0) population with the initial injection phase ϕ after interacting with a half laser pulse at 800 nm. The corresponding laser fields as functions of time for ϕ = 0, π∕4, π∕2 are respectively depicted. c dependence of the yield population on the injection instants within the full laser pulse. At these instants, the laser field takes local maximum at each individual optical cycle. The contour plot illustrates the transient ionic states that are polarized according to the instantaneous laser field.