Multiphoton resonant excitation of atoms in strong laser fields and implementation of coherent superposition states

Abstract

The multiphoton resonant excitation of three-level atoms in a strong laser field is investigated. The creation of various superposition states is shown. For implementation of these effects either the mean dipole moment in the excited states of an atom or, in three-level systems, a transition dipole moment between excited states (with energies close enough to each other) must be nonzero. The time evolution of the system is found using a nonperturbative resonant approach. Our calculations for the hydrogen atom suggest that by the appropriate optical pulses with moderate strong intensities one can achieve various superposition states by multiphoton resonant excitation.