部分相干高斯-谢尔模型光束在介质中传输的M^2因子  

M^2-Factor of Partially Coherent Gaussian Schell-Model Beams Propagating in Media

作　　者：文侨[1] 张彬[1] 

机构地区：[1]四川大学电子信息学院,成都610064

出　　处：《光学学报》2006年第2期212-216,共5页Acta Optica Sinica

基　　金：国家自然科学基金(60108004);四川省青年科技基金(05ZQ026-013)资助课题

摘　　要：在波数K为复数的情况下,对部分相干光强度二阶矩及M2因子的定义进行了修正。以部分相干高斯谢尔模型(GSM)光束为例,讨论了光束在介质中传输时M2因子的变化。研究结果表明,部分相干光束在增益或损耗介质中传输时的M2因子与光束在无增益无损耗介质传输时的M2因子具有不同变化特性,此时,M2因子不仅只与部分相干光的相干参量β有关,且随着传输距离B和表征介质增益(或损耗)特征Ki的增大而增大(或减小);随着相干长度σ0的具体尺寸、波数实部Kr的减小而增大(或减小)。为控制光束质量提供几种有效的途径。Considering Of the complex wave number, the second-order intensity moments and the M^2-factor of partially coherent beams have been modified. A partially coherent Gaussian Schell-model beam progating in media is taken as typical example to study the change of M^2 -factor. It can be shown that unlike in free-space, the M^2 -factor of partially coherent beams in the gain or absorbing media does not only depend on the coherent parameter β. In gain media, the M^2 -factor increases with the increase of the propagation distance B and the parameter characterizing the media ｜ Ki ｜ , and with the decrease of the coherent length ao and the wave number Kt, whereas in absorbing media, the M^2 -factor decreases with the increase of the propagation distance B and the parameter characterizing the media ｜ Ki ｜ , and with the decrease of the coherent length σ0 and the wave number Kt. The result can offer some effective methods of beam quality control.

关 键 词：激光技术 光束质量 复数波数 高斯-谢尔模型光束 肝因子 增益或损耗系数 

分 类 号：O436[机械工程—光学工程]