Chapter 8 - Nonlinear optical processes in materials

Abstract

So far we have focused our discussion on the interactions of electromagnetic waves with matter assuming that processes are dominated by the linear polarization equation given in Chapter 1. In this chapter, we perform a series expansion of the linear polarization expression to examine the effect of multiple fields on polarization in a medium. Such processes are nonlinear in nature and form the basis of nonlinear optical material interactions. We find that the type of nonlinear optical behavior exhibited by a material depends on its atomic structure and composition. Further, although a wide variety of different nonlinear effects are possible in a particular material system, in this chapter we examine the predominant processes that lead to nonlinear behavior and give examples of technologically important materials systems notable for their nonlinear optics properties.