Perturbation-variational approach to hydrogen atoms in strong laser fields

A perturbation variational approach (PVA) to atomic behavior in strong laser fields is expressed briefly. For the wide range of α0 = 0.1 → 50, the ground state energy of H-atom in laser fields is obtained by the present approach. The energy values obtained by PVA agree with the previous values given by Landgraf and Gavrila. In contrast, the advantage of the present method is to give both the energy eigenvalue and the wavefunction of the ground state analytically