双光子光折变介质中屏蔽光伏空间孤子

Screening-photovoltaic spatial soliton in two-photon photorefractive media

为了得到更完善的双光子屏蔽光伏孤子理论,采用光束的空间宽度不是远小于晶体宽度的条件,对有偏压的双光子光伏光折变介质中空间光孤子理论进行了修正,得出了明孤子和暗孤子数值积分解。结果表明,双光子屏蔽光伏孤子源于对外加电场的非均匀空间屏蔽和光伏效应,不同于起源于对外电场非均匀屏蔽的屏蔽孤子和起源于光伏效应的光伏孤子。当光伏效应被忽略时,屏蔽光伏孤子退化成屏蔽孤子,空间电荷场就是屏蔽孤子的空间电荷场;当外加电场为0时,屏蔽光伏孤子退化成开路或闭路的光伏孤子,空间电荷场就是晶体中的光伏场。

In order to obtain a more perfect theory of two-photon screening-pbotovoltic solitons, the theory of spatial solitons in biased two-photon photovoltaic photorefractive crystals were amended theoretically under the condition that spatial width of the beam was not much smaller than the width of crystal. The numerical integral solutions for both the bright and dark solitons were presented. The result shows that different from screening solitons originating from the spatially nonuniform screening of the external electric field and photovohaic solitons originating from the pbotovoltaic effect, two-photon screening photovoltaic solitons originates from both the spatially nonuniform screening of the external electric field and the photovohaic effect. When the photovohaic effect is neglected, the screening-photovohaic solitons are the screening ones and their space charge field is the space charge field of the screening solitons. When the external field is absent, the screening photovoltaic solitons are the photovoltaic ones on the open and closed circuit conditions and their space charge field is of the pbotovoltaic solitons