中国物理B ›› 2010, Vol. 19 ›› Issue (11): 114207-114209.doi: 10.1088/1674-1056/19/11/114207

• CLASSICAL AREAS OF PHENOMENOLOGY • 上一篇    下一篇

Nonlinear images of scatterers in chirped pulsed laser beams

胡勇华, 王友文, 文双春, 范滇元   

  1. School of Computer and Communication, Hunan University, Changsha 410082, China
  • 收稿日期:2009-11-24 修回日期:2010-05-24 出版日期:2010-11-15 发布日期:2010-11-15
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 60890202 and 10974049).

Nonlinear images of scatterers in chirped pulsed laser beams

Hu Yong-Hua(胡勇华), Wang You-Wen(王友文), Wen Shuang-Chun(文双春), and Fan Dian-Yuan(范滇元)   

  1. School of Computer and Communication, Hunan University, Changsha 410082, China
  • Received:2009-11-24 Revised:2010-05-24 Online:2010-11-15 Published:2010-11-15
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 60890202 and 10974049).

摘要: The bandwidth and the duration of incident pulsed beam are proved to play important roles in modifying the nonlinear image of amplitude-type scatterer. It is found that the initially positive chirp-type bandwidth can suppress the nonlinear image, while the negative one can enhance it, and that both effects are inversely proportional to the incident pulse duration. Numerical simulations further demonstrate that the location of nonlinear image is at the conjugate plane of the scatterer and that, for negatively pre-chirped pulsed beam, the nonlinear image peak intensity can be higher than that in the corresponding monochromatic case under certain conditions. Moreover the effect of group velocity dispersion on nonlinear image is found to be similar to that of chirp-type bandwidth.

Abstract: The bandwidth and the duration of incident pulsed beam are proved to play important roles in modifying the nonlinear image of amplitude-type scatterer. It is found that the initially positive chirp-type bandwidth can suppress the nonlinear image, while the negative one can enhance it, and that both effects are inversely proportional to the incident pulse duration. Numerical simulations further demonstrate that the location of nonlinear image is at the conjugate plane of the scatterer and that, for negatively pre-chirped pulsed beam, the nonlinear image peak intensity can be higher than that in the corresponding monochromatic case under certain conditions. Moreover the effect of group velocity dispersion on nonlinear image is found to be similar to that of chirp-type bandwidth.

Key words: pulsed laser beam, nonlinear propagation, nonlinear image, self-focusing

中图分类号:  (Imaging and optical processing)

  • 42.30.-d
42.60.Jf (Beam characteristics: profile, intensity, and power; spatial pattern formation) 42.65.Re (Ultrafast processes; optical pulse generation and pulse compression)