Theoretical study on non-sequential double ionization of carbon disulfide with different bond lengths in linearly polarized laser fields

By using a two-dimensional Monte-Carlo classical ensemble method, we investigate the double ionization (DI) process of the CS₂ molecule with different bond lengths in an 800-nm intense laser field. The double ionization probability presents a “knee” structure with equilibrium internuclear distance R=2.9245 a.u. (a.u. is short for atomic unit). As the bond length of CS increases, the DI probability is enhanced and the “knee” structure becomes less obvious. In addition, the momentum distribution of double ionized electrons is also investigated, which shows the momentum mostly distributed in the first and third quadrants with equilibrium internuclear distance R=2.9245 a.u. As the bond length of CS increases, the electron momentum becomes evenly distributed in the four quadrants. Furthermore, the energy distributions and the corresponding trajectories of the double-ionized electrons versus time are also demonstrated, which show that the bond length of CS in the CS₂ molecule plays a key role in the DI process.