Close Coupled Channels Method: For Hydrogen Atom in Strong Laser Fields

The interaction of short laser pulses with hydrogen atoms will be discussed in this paper. We chose laser pulses with photon energies lower than the ionization threshold energy of hydrogen atoms. Here, the close coupled channel method is used to solve the time-dependent Schrödinger equation. Our goal is to demonstrate how this approach can be used to calculate the phenomenon of multiphoton absorption-induced excitation to the 2S and 2P states. It was also shown how the probability of excitation depends on the duration and strength of the laser pulse. This approach exhibits good agreement when compared to the findings of other studies.