Two-photon double ionization of helium by chirped few-cycle attosecond pulses: From nonsequential to sequential regime

Tong Yao¹, Jiang Wei-Chao^{1, 2}, Wu Pan¹, Peng Liang-You^{1, 3, †,}

The vector potentials of the laser pulses for ξ = 0 and ± 1.75. In this example, we take the central frequency ω₀ = 52.4 eV, the peak intensity I₀ = 1×10¹⁵ W/cm², and τ₀ = 460 as.