中国物理B ›› 2014, Vol. 23 ›› Issue (6): 64209-064209.doi: 10.1088/1674-1056/23/6/064209

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

A further study on the spreading and directionality of Gaussian array beams in non-Kolmogorov turbulence

陆璐, 季小玲, 邓金平, 李晓庆   

  1. Department of Physics, Sichuan Normal University, Chengdu 610066, China
  • 收稿日期:2013-09-21 修回日期:2013-11-04 出版日期:2014-06-15 发布日期:2014-06-15
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 61178070) and the Construction Plan for Scientific Research Innovation Teams of Universities in Sichuan Province, China (Grant No. 12TD008).

A further study on the spreading and directionality of Gaussian array beams in non-Kolmogorov turbulence

Lu Lu (陆璐), Ji Xiao-Ling (季小玲), Deng Jin-Ping (邓金平), Li Xiao-Qing (李晓庆)   

  1. Department of Physics, Sichuan Normal University, Chengdu 610066, China
  • Received:2013-09-21 Revised:2013-11-04 Online:2014-06-15 Published:2014-06-15
  • Contact: Ji Xiao-Ling E-mail:jiXL100@163.com
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 61178070) and the Construction Plan for Scientific Research Innovation Teams of Universities in Sichuan Province, China (Grant No. 12TD008).

摘要: It is found that in free space, the curves of the mean-squared beam width may each have a cross point at a certain propagation distance zc. For Gaussian array beams, the analytical expressions of zc are derived. For the coherent combination, zc is larger than that for the incoherent combination. However, in non-Kolmogorov turbulence, the cross point disappears, and the Gaussian array beams will have the same directionality in terms of the angular spread. Furthermore, a short propagation distance is needed to reach the same directionality when the generalized exponent is equal to 3.108. In particular, it is shown that the condition obtained in previous studies is not necessary for laser beams to have the same directionality in turbulence, which is explained physically. On the other hand, the relative average intensity distributions at the position where the Gaussian array beams have the same mean-squared beam width are also examined.

关键词: cross point of curves of the mean-squared beam width, spreading and directionality, non-Kolmogorov turbulence, Gaussian array beams

Abstract: It is found that in free space, the curves of the mean-squared beam width may each have a cross point at a certain propagation distance zc. For Gaussian array beams, the analytical expressions of zc are derived. For the coherent combination, zc is larger than that for the incoherent combination. However, in non-Kolmogorov turbulence, the cross point disappears, and the Gaussian array beams will have the same directionality in terms of the angular spread. Furthermore, a short propagation distance is needed to reach the same directionality when the generalized exponent is equal to 3.108. In particular, it is shown that the condition obtained in previous studies is not necessary for laser beams to have the same directionality in turbulence, which is explained physically. On the other hand, the relative average intensity distributions at the position where the Gaussian array beams have the same mean-squared beam width are also examined.

Key words: cross point of curves of the mean-squared beam width, spreading and directionality, non-Kolmogorov turbulence, Gaussian array beams

中图分类号:  (Atmospheric turbulence effects)

  • 42.68.Bz
42.25.Bs (Wave propagation, transmission and absorption) 42.25.Dd (Wave propagation in random media)