Second-harmonic generation in multilayered devices: theoretical tools

We present theoretical aspects of the study of nonlinear multilayered dielectric devices. Starting from Maxwell's equations, we write the propagation equations for the pump and the harmonic fields without any approximation. We show that we can consider the two fundamental cases of TE and TM polarization. Using a suitable transfer matrix formalism, we solve the propagation equations for the undepleted cases for both a plane incident wave and a spatially limited incident beam. The case of a depleted-pump wave is also considered. Numerical simulations are carried out for a prism coupler. They show the limits of each approximation and also emphasize the advantages of multilayered devices for second-harmonic generation. Finally, we show the usefulness of the model compared with experimental results. We concentrate on second-harmonic generation by zinc sulfide thin films. (C) 1998 Optical Society of America.