Phase-dependent nonsequential double ionization by few-cycle laser pulses

By solving the time-dependent Schrödinger equation, we investigate the phase dependence of nonsequential double ionization of one-dimensional Ar atoms by linearly polarized few-cycle pulses. The resulting two-electron momentum distributions exhibit a strong dependence on the pulse's carrier-envelope phase (CEP). The calculated Ar²⁺ ion momentum distributions parallel to the laser polarization direction are in good agreement with the experimental measurements of Liu et al (2004 Phys. Rev. Lett. 93 263001). The ratio of the total double ionization yields from the first and third quadrants as a function of the CEP is similar to the ratio of the total single ionization yields from the left and right sides. The influence of electron–electron Coulomb repulsion on double ionization is also investigated by comparing a short-range interaction with the infinite-range interaction. Our theoretical simulations provide a prediction for determining the CEP value of few-cycle pulses by comparing with the experimental measurements.