Fig. 1. Momentum distributions of two electrons at different laser intensities for an Ar atom irradiated by CRTC laser wavelengths of 790 nm and 395 nm. For (a) and (b), the laser intensity is chosen as I0=2×1014W/cm2 and 4×1014W/cm2, respectively. The two colors are of equal intensity.

Fig. 2. Momentum distributions of two electrons from a Ne atom irradiated by CRTC laser wavelengths of 498 nm and 249 nm, with laser intensities (a) 5.04×1014W/cm2, (b) 7.99×1014W/cm2, and (c) 1.27×1015W/cm2, respectively. The He atoms are irradiated by CRTC laser wavelengths of 366 nm and 183 nm, with laser intensities (d) 9.28×1014W/cm2, (e) 1.99×1015W/cm2, and (f) 4.31×1015W/cm2, respectively. The two colors are of equal intensity.

Fig. 3. Momentum distribution of two electrons from a Ne atom irradiated by CRTC laser wavelengths of 498 nm and 249 nm, with laser intensities (a) 1.01×1015W/cm2, (b) 1.59×1015W/cm2, and (c) 2.54×1015W/cm2, respectively. The He atom irradiated by CRTC laser wavelengths of 366 nm and 183 nm, with laser intensities (d) 1.86×1015W/cm2, (e) 3.99×1015W/cm2, and (f) 8.62×1015W/cm2. The two colors are of equal intensity.

Fig. 4. MDP in four quadrants for Ar atoms, Ne atoms, and He atoms. (a) and (c) show the MDP of Ar atoms at CRTC laser intensities I0=2×1014W/cm2 and 4×1014W/cm2, respectively, compared with Ne atoms at laser intensities k2I0, k3I0, and k4I0, respectively. (b) and (d) show the MDP of He atoms with the same parameters as (a).

Fig. 5. Momentum distribution of two electrons from a Ne atom irradiated by CRTC laser intensity of 7.99×1014W/cm2, with laser wavelengths of (a) 790 nm and 395 nm, (b) 314 nm and 157 nm, respectively. (c) and (d) show the momentum distribution of two electrons from a He atom irradiated by CRTC laser intensity of 1.99×1015W/cm2, with laser wavelengths of (c) 790 nm and 395 nm, (d) 170 nm and 85 nm, respectively.

Table 1. Values of Softening Parameters a, b and Hamiltonian of a Two-Electron Atom Used in This Letter