| Before laser was invented, people's knowledge of optics was within the limits of linear optics. After laser came out, nonlinear optics turned up in the world as a new branch subject of optics. During short forty years, nonlinear optics was greatly developed in basic principle, study of new-type material, discovery and application of new effect, and became one of the most active and important branches in optical field. In this thesis, according to nonlinear optics foundational theory, we talk about some current important nonlinear optical effects including double frequency effect, optical rectification effect and linear electro-optic effect, then we have studied the nonlinear optical properties of new semiconducting material, cubic boron nitride (cBN), with these nonlinear optics effects. Cubic boron nitride has zinc-blende structure and symmetry and it doesn't possess center of inversion, consequently, cBN can produce second order nonlinear optical effects. Second order nonlinear optical properties of cBN will be widely applied the future in the optoelectronics field, because cBN is transparent in the whole visible light spectrum and infrared spectrum and the large range of ultraviolet spectrum. However, we haven't seen any reports about the study of the second order nonlinear optical properties of cBN up to now. The study on semiconducting property of cBN, which is a new type artificial synthetic and wide band-gap semiconducting material, hasn't largely developed, and the study on cBN in nonlinear optical field is much less. To realize the optical properties of cBN more comprehensively, we have made use of nonlinear optical principle to study the nonlinear optical properties of cBN, and acquired some developments. This will help to more roundly understand the optical properties of wide band-gap semiconducting material—cBN.Linear electro-optic effect, namely Pockels effect, is a special second order nonlinear optical effect. With two electrical fields in which one is optical wave electrical field and another is low frequency electrical field or dc electrical field, cBN can produce second order nonlinear polarization. For the settled shape of cBN, we have educed in theory that cBN has linear electro-optic effect when there exist applied dc electrical field in the cBN [111] orientation, and observed evident linear electro-optic effect for the first time when we use He-Ne laser to operate transverse electro-optic modulation experiment on cBN, and obtained that output of optical intensity linearly depend on modulation voltage. We have also calculated half wave voltage, linear electro-optic coefficient and secondary nonlinear polarization coefficient of cBN sample from the experimental result obtained. These parameters obtained complement some properties of cBN in the nonlinear optics field.Both double frequency effect, namely second harmonic generation, and optical rectification effect belong to the second order nonlinear optics effects. Second harmonic generation is the most typical, important and elementary technique in nonlinear optics mixed frequency, and also a technique applied widely. Optical rectification is a phenomenon that the dc component of second order nonlinear electrical polarization is produced with an optical wave. We have deduced with the second harmonic generation and optical rectification theory that double frequency and optical rectification polarizations hadn't vanished in cBN with light irradiating perpendicular and parallel to the cBN (111) plane, therefore cBN should have second harmonic generation and optical rectification effect at the action of strong laser light. We have also assuredly observed green double frequency light and measured the signal of optical rectification with modulated Q pulse laser. We design the optical rectification experiment aimed at measuring the second order nonlinear coefficient of cBN, and we will continue to demonstrate the experiment in the future, and compare this coefficient with the second order nonlinear coefficient obtained with linear e...
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