Consecutive quasi-phase-matched interactions of light waves in periodically poled nonlinear optical crystals

A new type of quasi-phase-matched interactions of light waves is considered - consecutive interactions of waves with frequencies omega, 2 omega, 3 omega and omega, 2 omega, 4 omega. They are shown to be possible in a periodically poled LiNbO3:Y:Mg crystal for both co- and counterpropagating waves. It is shown that under certain conditions the energy of a high-intensity pump wave in the consecutive three-frequency interactions under consideration can be completely converted to the energy of one of the other two waves.