Relativistic theory of the above-threshold multiphoton ionization of hydrogen-like atoms in the ultrastrong laser fields

摘要

The relativistic theory of above-threshold ionization (ATI) of hydrogen-likeatoms in ultrastrong radiation fields, taking into account the photoelectroninduced rescattering in the continuum spectrum is developed. It is shown thatthe contribution of the latter in the multiphoton ionization probability evenin the Born approximation by Coulomb field is of the order of ATI probabilityin the scope of Keldysh-Faisal-Reiss ansatz.