二维随机激光器的模式选择及阈值与饱和特性  

Threshold and saturation properties of two-dimensional random lasers and mode selection

作　　者：刘劲松[1] 刘海[1] 王春[1] 吕健滔[1] 樊婷[1] 王晓东[1] 

机构地区：[1]华中科技大学激光技术国家重点实验室,武汉430074

出　　处：《物理学报》2006年第8期4123-4131,共9页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:60378001);湖北省自然科学基金重点项目(批准号:2001ABA003)资助的课题.~~

摘　　要：基于将Maxwell方程与四能级原子系统速率方程相结合而建立起随机激光时域理论,并利用有限时域差分法,研究了二维随机介质中激光模式的输出特性与介质尺寸、外形及抽运速率等参数的关系.结果表明,与传统激光模式相似,随机激光模式的强度随抽运速率的变化不仅具有阈值特性,而且具有饱和特性.基于模式特性对介质及抽运参数的依赖关系,提出了二维随机激光器的选模方式,在很大程度上不同于传统激光器的选模方式.Based on the time dependent theory of random lasers, which was established via combining Maxwell equations with the rate equations of a four-level atomic system, the output intensity of lasing modes varying with the pump rate and area as well as the medium＇s size and shape is simulated for two-dimensional random media by use of the finite difference time domain method. Results show that the pump-rate dependence of the output intensity presents not only a threshold property, but also a saturation property, just like that of the lasing modes in conventional lasers. Based on the dependence of mode property on the medium＇s and pump＇s parameters, the mode-selection approaches are proposed for two-dimensional random lasers, which are quite different from those performed in conventional lasers.

关 键 词：随机激光器 模式选择 无序介质中的光学特性 

分 类 号：TN248[电子电信—物理电子学] TN241