Measurement of the nonlinear susceptibility of various molecular crystals using the method of "frequency" interference fringes

An analysis is made of the feasibility of measuring the components of the nonlinear susceptibility tensor by observing oscillations of the second harmonic intensity as a function of the frequency of the converted signal. It is shown that if the dispersion of the refractive indices is known, the components of the nonlinear susceptibility can be measured with the same accuracy as that obtained using Maker's fringes. This method is less sensitive to the quality of the samples and to the divergence of the optical beam. Measurements were made of the components of the nonlinear susceptibility tensor of various molecular crystals.