ABSTRACT
This chapter introduces the ‘effective’ second order nonlinear susceptibility coefficient, deff. It provides the coefficients of all 18 elements of the d matrix in the expression for deff for three cases of phase matched three wave interaction for propagation along principal planes of a biaxial crystal. The chapter also provides the coefficients of all 18 elements of the d matrix in the expression for deff for three cases of phase matched three wave interaction for propagation in an uniaxial crystal. It presents the expressions for deff for propagation along principal planes of some biaxial crystals. The chapter presents the expressions for deff for propagation in some uniaxial crystals. It describes the expressions for deff for propagation in isotropic crystals. The chapter outlines the deff values for biaxial and uniaxial crystals for the cases of birefringent phase matched three wave mixing processes, that is, with the highest frequency beam of light traveling as a ‘fast’ wave in the crystal.
