暗光伏孤子的实验研究

Experimental study on dark photovoltaic solitons

在LiNbO3∶Fe晶体中,采用相位掩模对部分空间非相干和相干暗光伏孤子进行了实验研究.实验观察到了部分空间非相干和相干的一维和二维暗光伏孤子,它们的形成来源于光伏效应,是自散焦效应和衍射效应平衡的结果.实验和理论分析表明,暗光伏孤子的形成与光的传输方向,强度梯度与晶体c轴夹角有关;只有在一定的条件下,才能得到稳态的部分空间非相干暗光伏孤子.

Spatially partially incoherent and coherent dark photovoltaic solitons are comprehensively experimentally studied with phase masks in LiNbO3 ： Fe crystals. One-dimension and two-dimension dark photovoltaic solitons are observed with spatially partially incoherent and coherent beam,which result from the bulk photovoltaic effect and when diffraction is exactly balanced by photorefractive self-defocusing. The analysis of theory and experiments shows that dark photovoltaic solitons depend on the direction of propagation, orientation of the intensity gradient, with respect to the crystalline axes of the medium. Under certain conditions, the steady-state spatially partially incoherent dark photovoltaic solitons can be observed.