Nonlinear optics from the viewpoint of interaction time

In recent decades, progress in developing better nonlinear materials has not been as rapid as wished. Here I propose that this may be explained by considering the simple view of nonlinear optical phenomena as being determined mostly by the length of interaction time between photons and matter. Tentative routes towards improvements in the efficiency of nonlinear optical phenomena are suggested.

Automated summary

In recent decades, progress in developing better nonlinear materials has been slower than desired. The author suggests that this may be due to the length of interaction time between photons and matter being the main determinant of nonlinear optical phenomena. Tentative approaches to improve the efficiency of nonlinear optical phenomena are proposed.