Tunable self-action of light in optical rectification

We analyze the self-action of light waves mediated by cascaded optical rectification in a quadratic nonlinear crystal in the framework of the full local-field equations and show that the process can lead to a rich variety of self-effects. We put forward a general scheme to calculate the full nonlinear response mediated by the self-generated rectified fields and thus show that acting on the shape, the polarization of the light beam and the geometric arrangement of the nonlinear crystal allows tuning the sign, the strength, and the type of the induced nonlinearities, opening the door to the exploration of a variety of self- and cross-phase modulations, and solitary-waves. We also show configurations where even though the macroscopic rectified field vanishes, the macroscopic self-effects do not.Peer Reviewe