4-PHOTON PARAMETRIC INTERACTION UNDER THE CONDITION OF MAGNETIC SUBLEVEL COHERENCE

The influence of the atom magnetic sublevel coherence on the nondegene rate four-wave parametric light scattering has been theoretically inve stigated taking into account the multiplet structure of the excited st ate. The theory is based on the irreducible tensorial formalism that a llows us to take into consideration the relaxation related to both the nonuniform population and Zeeman coherence between the magnetic suble vels. The coefficient of the wave parametric coupling has been studied and three physical mechanisms (normal population, cross population an d Zeeman coherence) are discussed. The results can be used, in particu lar, in high-resolution spectroscopy of the dipole-forbidden transitio ns.