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The objective of this thesis is to provide a modified Kurtz method for measuring the indices of refraction and the effective second harmonic generation coefficients of powder materials. We used a liquid waveguide to measure the relation of the intensity of the scattered second harmonic generation and the qverage particle sizes, The experimental results were fitted by our empirical formula to estimate the effective second harmonic generation coefficient, the dispersion of fundamental and second harmonic waves, as well as to determine whether the material is a phase matchable one. We used the crystalline powder materials KDP, BBO, Urea, LiNbO3 and crystalline quartz as the standard samples. By comparing with the generally recognized values of corresponding properties of the bulk crystals, the error from the measurement of the index of refraction is less than 5% and those of the effective second harmonic gescration coefficient and dispersion are less than 10% The linear and nonlinear optical properties of new quaternary materials (Ba, Sr) TiO3 (BST) were studied by our modified method The experimental results showed that the index of refraction of Ba0.8Sr0.2TiO3 is 1.87, the effective second harmonic generation coefficient is 4.77 times of the BBO's, and it is a phase matchable material with good nonlinear optical properties.
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