Analysis of angular dependence of strong-field tunneling ionization for ${\text{CO}}_2$

We analyzed the discrepancy of the angular dependence of strong-field ionization for ${\text{CO}}_2$ among the different theoretical calculations and experiments. Using a more accurate ground-state wave function of ${\text{CO}}_2$ in the asymptotic region, we showed that the accuracy in the earlier tunneling ionization theory of Tong et al. [Phys. Rev. A 66, 033402 (2002)] is much improved. We also concluded that the angular dependence deduced from the experiment of Pavičić et al. [Phys. Rev. Lett. 98, 243001 (2007)] appears to be too narrowly distributed.

Figure 1

(Color online) Partial wave radial function of ${\text{CO}}_2$: (a) small-$r$ region; (b) large-$r$ region. The solid lines are from the present results, and dashed lines are calculated with GAMESS code. For clarity, in (b), the radial function for $l=4\left(l=6\right)$ is divided by ${10}^2\left({10}^4\right)$.

Figure 2

(Color online) The normalized alignment dependence of ionization rate of ${\text{CO}}_2$. The laser intensity is $2\times {10}^{14}\text{W}/{\text{cm}}^2$. MO-ADK and SFA from [12].

Figure 3

(Color online) The normalized alignment dependence of ionization probability of ${\text{CO}}_2$. (a) Laser intensity is $1.1\times {10}^{14}\text{W}/{\text{cm}}^2$; (b) laser intensity is $0.5\times {10}^{14}\text{W}/{\text{cm}}^2$. Note that $0.56\times {10}^{14}$ and $0.3\times {10}^{14}\text{W}/{\text{cm}}^2$ were used in [13, 6], respectively. ${\text{Experiment}}^a$ from [5], ${\text{TDSE}}^b$ from [14], ${\text{TDSE}}^c$ from [13], and ${\text{Experiment}}^d$ from [6].

Figure 4

(Color online) Normalized alignment dependence of ionization probability of ${\text{H}}_2^{+}$ at laser intensity of $5\times {10}^{14}\text{W}/{\text{cm}}^2$. ${\text{TDSE}}^a$ from [22] and ${\text{TDSE}}^b$ from [23].