中心对称和非中心对称单光子光折变空间屏蔽灰孤子的时间特性  

Temporal behavior of the screening grey spatial solitons in one-photon centrosymmetric and non-centrosymmetric photorefractive crystals

作　　者：吉选芒[1] 姜其畅[1] 苏艳丽[1] 刘劲松[2] 

机构地区：[1]山西运城学院物理与电子工程系,山西运城044000 [2]华中科技大学光电子科学与工程学院,湖北武汉430074

出　　处：《红外与激光工程》2013年第1期63-68,共6页Infrared and Laser Engineering

基　　金：山西省自然科学基金(2011011003-2);山西省高校科技研究开发项目(20111125)

摘　　要：为了得到中心对称和非中心对称外加电场单光子光折变晶体中空间屏蔽灰孤子时间特性的结果,基于中心对称和非中心对称单光子光折变效应的基本理论,推导出了含时间参量的空间电荷场和光波的动态演化方程,采用数值方法,分别研究了基于中心对称和非中心对称单光子光折变晶体中灰孤子强度包络和强度半峰全宽的时间特性。结果表明:当孤子的峰值强度与暗辐射的比值较大时,孤子的半峰全宽先是随时间递减到一个最小值,然后逐渐增加到一个稳定的常数值。当孤子的峰值强度与暗辐射的比值较小时,孤子的半峰全宽随时间的增加而单调减小,最终达到一稳定状态。对不同时刻灰孤子的动态演化特性进行了研究,中心对称和非中心对称空间灰孤子有类似的时间演化特性。In order to study the temporal behavior of screening gray spatial solitons in biased one-photon centrosymmetric and non-centrosymmetric photorefractive crystals, the expressions of time-dependent space-charge field and dynamical evolution equation were deduced based on one-photon centrosymmetric and non-centrosymmelric photorefractive effect. The temporal behavior of the intensity profiles and the intensity full width at half maximum （FWHM） of gray solitons were studied by numerical method. The results indicate that, when the ratio between the soliton peak intensity and dark irradiance is larger, the FWHM of solitons first decreases to a minimum and then increases to a constant value; when the ratio between the soliton peak intensity and dark irradiance is smaller, the FWHM of gray solitons decreases monotonously with the increase of time toward steady state. Dynamical evolutions of the grey spatial solitons are simulated numerically at different time. Centrosymmetric and non-centrosymmetric gray solitons have the similar temporal properties.

关 键 词：非线性光学 中心对称和非中心对称光折变介质 空间孤子 时间行为 

分 类 号：O437[机械工程—光学工程]