摘要
建立了受激布里渊散射介质中热作用破坏的物理模型,数值模拟了杂质颗粒的温度随其半径的变化曲线.结果显示,杂质颗粒存在一个最大热作用半径,介质所含颗粒的尺寸在此半径附近时,介质最容易发生光学击穿现象,其光学击穿阈值最低.在Continuum Nd:YAG种子注入式激光系统中,选取FC-3283,GF-180和HFE-7100介质,通过不同孔径的过滤膜进行过滤,并研究了过滤前后的光学击穿阈值和能量反射率.结果表明,随着过滤孔径的变小,介质光学击穿阈值逐渐提高,且过滤之后介质的能量反射率有了明显的提高.介绍了一种利用He-Ne激光透射光光斑变化来判断是否发生光学击穿现象的方法,该方法具有方便、准确的特点,可有效地减小由于肉眼观测引起的误差.
In this paper,we establish the physical model of hot damage to the stimulated Brillouin scattering(SBS) medium,and with numerical simulation method the curve of the temperature of impurity particles versus the radius is investigated.The result indicates that impurity particle has a maximal thermal effect radius and when the sizes of particles contained in the medium are near the radius, the optical breakdown phenomenon is most likely to appear,and at this point the optical breakdown threshold is lowest.We use FC- 3283,GF-180 and HFE-7100 as the SBS medium in Continuum Nd:YAG laser system.The SBS medium passes through the filter with different diameters.We study the optical breakdown thresholds and energy reflectivities before and after filtration.It is demonstrated that with the filter diameter decreasing,the optical breakdown threshold increases gradually and the energy reflectivity is significantly improved through filter.In addition,a method of using He-Ne laser transmission light spot size to judge whether optical breakdown phenomenon happens,is also developed.This method is convenient and accurate,and can effectively reduce the error caused by naked eye observation.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2012年第14期221-226,共6页
Acta Physica Sinica
基金
国家自然科学基金(批准号:61138005
21071035)
新世纪优秀人才支持计划(批准号:NCET-08-0173)
中央高校基本科研业务费专项资金(批准号:HIT.BRET2.20100/2)资助的课题~~
关键词
受激布里渊散射介质
杂质颗粒
光学击穿阈值
stimulated Brillouin scattering
SBS medium
impurity particles
optical breakdown threshold value