Abstract In this paper, we investigate the modulation instability for generating femtosecond pulses in fibres with slowly decreasing dispersion. Higher-order dispersion and higher-order nonlinear effects are taken into account when the continuous wave or quasi-continuous wave evolves into sub-picosecond and femtosecond pulses by modulation instability in the optical fibres. Our research results show that the gain spectrum of the dispersion-decreasing fibres is much wider than that in conventional fibres. The third-order dispersion effect has no contribution to gain spectrum, while the self-steepening effect reduces the maximum value and gain bandwidth, and the Raman self-scattering effect widens the extent to which the modulation instability occurs.
Received: 18 April 2001
Revised: 05 September 2001
Published: 12 June 2005
(Dynamics of nonlinear optical systems; optical instabilities, optical chaos and complexity, and optical spatio-temporal dynamics)
(Ultrafast processes; optical pulse generation and pulse compression)
Fund: Project supported by the Natural Science Foundation of Guangdong Province, China (Grant No. 980030), and the Natural Science Foundation of the Education Bureau of Guangdong Province, China (Grant No. 200019).
Cite this article:
Zhang Shu-Min, Xu Wen-Cheng, Chen Wei-Cheng, Luo Ai-Ping, Guo Qi, Liu Song-Hao Modulation instability of femtosecond pulses in fibres with slowly decreasing dispersion 2002 Chin. Phys. 11 39