中国物理B ›› 2001, Vol. 10 ›› Issue (11): 1032-1036.doi: 10.1088/1009-1963/10/11/308

• CLASSICAL AREAS OF PHENOMENOLOGY • 上一篇    下一篇

FILAMENTATION INSTABILITY OF LASER BEAMS IN NONLOCAL NONLINEAR MEDIA

文双春, 范滇元   

  1. National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
  • 收稿日期:2001-03-16 修回日期:2001-06-08 出版日期:2005-06-12 发布日期:2005-06-12
  • 基金资助:
    Project supported by the National High Technology Inertial Confinement Fusion Foundation of China (Grant No. 863-416-5) and the National Natural Science Foundation of China (Grant No. 69789801).

FILAMENTATION INSTABILITY OF LASER BEAMS IN NONLOCAL NONLINEAR MEDIA

Wen Shuang-chun (文双春), Fan Dian-yuan (范滇元)   

  1. National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
  • Received:2001-03-16 Revised:2001-06-08 Online:2005-06-12 Published:2005-06-12
  • Supported by:
    Project supported by the National High Technology Inertial Confinement Fusion Foundation of China (Grant No. 863-416-5) and the National Natural Science Foundation of China (Grant No. 69789801).

摘要: The filamentation instability of laser beams propagating in nonlocal nonlinear media is investigated. It is shown that the filamentation instability can occur in weakly nonlocal self-focusing media for any degree of nonlocality, and in defocusing media for the input light intensity exceeding a threshold related to the degree of nonlocality. A linear stability analysis is used to predict the initial growth rate of the instability. It is found that the nonlocality tends to suppress filamentation instability in self-focusing media and to stimulate filamentation instability in self-defocusing media. Numerical simulations confirm the results of the linear stability analysis and disclose a recurrence phenomenon in nonlocal self-focusing media analogous to the Fermi-Pasta-Ulam problem.

Abstract: The filamentation instability of laser beams propagating in nonlocal nonlinear media is investigated. It is shown that the filamentation instability can occur in weakly nonlocal self-focusing media for any degree of nonlocality, and in defocusing media for the input light intensity exceeding a threshold related to the degree of nonlocality. A linear stability analysis is used to predict the initial growth rate of the instability. It is found that the nonlocality tends to suppress filamentation instability in self-focusing media and to stimulate filamentation instability in self-defocusing media. Numerical simulations confirm the results of the linear stability analysis and disclose a recurrence phenomenon in nonlocal self-focusing media analogous to the Fermi-Pasta-Ulam problem.

Key words: filamentation instability, nonlocal nonlinearity, nonlinear propagation

中图分类号:  (Beam trapping, self-focusing and defocusing; self-phase modulation)

  • 42.65.Jx
42.65.Sf (Dynamics of nonlinear optical systems; optical instabilities, optical chaos and complexity, and optical spatio-temporal dynamics) 42.60.Jf (Beam characteristics: profile, intensity, and power; spatial pattern formation) 42.60.Lh (Efficiency, stability, gain, and other operational parameters)