Attosecond pulse generation from two-electron harmonic emission spectrum*
Feng Li-Qianga),b)†, Liu Hangc)‡
       
HHG spectra from the two-electron He atom (solid black line) and the SEA He model (dash red line). The laser field is 5 fs/800 nm, I 1 = 5.0 × 1014 W/cm2.