Recollision induced excitation-ionization with counter-rotating two-color circularly polarized laser field

Effect of elliptical polarizations on nonsequential double ionization in two-color elliptically polarized laser fields

“…2(h)) due to the shape of the electric fields of the counterrotating TCCP laser fields, which has been presented in the theoretical study and the experimental observations. [37,38] Figure 3 shows that the correlated electron momentum distributions along the x direction and the ion momentum distributions of Mg atoms do not change obviously as the ellipticity increases, which is different from Ar atoms as shown in Fig. 2.…”

“…with the maximum combined electric field amplitude E 0 , the electric field amplitude ratio γ E = 1.4 [38] between the second harmonic laser pulse and the fundamental laser pulse, the fundamental frequency ω r = 0.0576 a.u. (790 nm in wavelength), and the second harmonic frequency ω b = 0.115 a.u.…”

“…[33] Up to now, it has been reported experimentally that the NSDI events in counter-rotating TCCP laser pulse has been realized and the theoretical analysis of the NSDI events characteristic has been illustrated. [34][35][36][37][38] Furthermore, HHG has been theoretically and experimentally illustrated by a bichromatic elliptically polarized laser field. [39,40] In addition, there are very many variable parameters in the counter-rotating TCCP laser fields, such as elliptical polarization, relative intensity, and phase.…”

Relative phase effect of nonsequential double ionization in Ar by two-color elliptically polarized laser field*

“…Because the net momentum of the electroneutral ionelectron system is zero, so we can obtain the relationship 𝑝 Ar 2+ = −(𝑝 e1 + 𝑝 e2 ). [36] Figure 3 shows the ion momentum distribution with three different relative phases at the end of the laser pulse in counter-rotating two-color laser fields at the laser peak intensity I 0 = 0.2 PW/cm 2 , and the red lines represent the negative vector potential −A(t) of the electric field. For the relative phase ∆ϕ = 0.4π, figure 3(a) shows that the shape of the ion momentum distribution is consistent with the negative vector potential which looks like number "8" with a small titled angle.…”

“…The electric field amplitude ratio γ E is chosen to be 1.4, which ensures that the probability of double ionization reaches the maximum. [36] f (t) = sin 2 (πt/nT ) is the envelope of the laser pulse and T is optical cycles (o.c.) of the fundamental laser field.…”