中文摘要：

研究了线性和二次电光效应共存的双光子光折变介质中沿同一直线传播的两空间光孤子间的相干耦合现象,从理论上证实了在适当的条件下相干耦合的亮-亮和暗-暗孤子对的存在。结果表明,这些相干耦合孤子对的形成、性质和传输规律依赖于介质内线性和二次电光效应间的相互作用（即相互增强、减弱甚至抵消）。详细分析了两相干入射光的初始相位差、强度比和外加电场等三个方面对相干耦合孤子对宽度及亮-亮孤子对的自转向过程的影响,为相干耦合孤子对在实际中的应用奠定理论基础。

英文摘要：

The coherent coupling of two spatial solitons propagating along the same line in biased two-photon photorefractive crystals with both the linear and quadratic electro-optic effects was investigated. It was proved that coherently coupled dark-dark and bright-bright spatial optical soliton pairs can be supported in the steady regime under appropriate conditions. These soliton pairs owe their existence and properties to the co-effects of both the linear and quadratic electro-optic effects where photorefractive effect may be enhanced, weakened or even counteracted because of the interaction of these two electro-optic effects. Moreover, the effects of the externally applied electric field, the initially phase difference and the intensity ratio of the two coherent beams on the existence conditions, properties of these spatial soliton pairs and self-deflection of coherently coupled bright-bright soliton pairs were discussed in detail,which lays the theoretic foundation for practical application of coherently coupled spatial soliton pairs.