非对称光折变全息空间光孤子的存在曲线

证明了在加外电场的光折变晶体中存在非对称全息空间光孤子对，其特征是孤子对中的两个 孤子具有相同的宽度、不同的振幅.给出了这种孤子对的存在曲线，其中存在三个具有不同 特征的区域：对于给定的外加电场来说，当孤子对中两个孤子的入射峰值强度之和与背景光 强度之比足够大或者足够小时，孤子宽度强烈依赖于这个比值，而在此中间的一段区域，孤 子宽度几乎不随这个比值而变化.非对称情况下这个中间区域的范围比对称情况的窄. 关键词： 空间光孤子 光折变非线性光学 全息光栅

Existence curves of asymmetric photorefractive holographic spatial optical solitons

It has been proved that there exist asymmetric holographic spatial optical soliton pairs in biased photorefractive crystals. The two solitons from such a pair have equal width and unequal amplitudes. The soliton existence curves of such soliton pairs are given and three regions of different behaviors exist in these curves. That is, for a given value of bias field, the width of holographic solitons depends strongly on the ratio of the total peak input intensity of the two solitons from a pair to the intensity of the background light when the ratio is small or large enough, whereas it remains relatively constant in a middle region. The extent of the middle region for the asymmetric case is smaller than that for the symmetric case.