[1] A. Hasegawa and F. Tappert, Appl. Phys. Lett. 23, 142; 171 (1973).

[2] L. F. Mollenauer, R. H. Stolen, and J. P. Gordon, Phys. Rev. Lett. 45, 1095 (1980).

[3] G. P. Agrawal, Nonlinear Fiber Optics (Academic Press, San Diego, 1995).

[4] A. Hasegawa and Y. Kodama, Solitons in Optical Communication (Oxford Universty Press, New York, 1995).

[5] S. L. Palacios and J. M. Fernandez-Diaz, J. Mod. Opt. 48, 1691 (2001).

[6] D. Pushkarov and S. Tanev, Opt. Commun. 124, 354 (1996).

[7] V. I. Karpman, Phys. Rev. E 62, 5678 (2000).

[8] H. W. Schurmann, Phys. Rev. E 54, 4312 (1996).

[9] X. P. Xie, S. H. Zhao, X. H. Wang, and G. F. Chen, Acta Photon. Sin. (in Chinese) 31, 429 (2002).

[10] V. I. Karpman, Phys. Lett. A 244, 397 (1998).

[11] S. Liu and W. Wang, Phys. Rev. E 49, 5726 (1994).

[12] H.-M. Li, Y.-S.Xu, and J. Lin, Commun. Theor. Phys. 41, 829 (2004).

[13] Z. J. Ren, J. Wang, A. L. Yang, L. Z. Wang, and J. Wang, Acta Photon. Sin. (in Chinese) 33, 758 (2004).

[14] M. Gedalin, T. C. Scott, and Y. B. Band, Phys. Rev. Lett. 78, 448 (1997).

[15] S. L. Palacios, A. Guinea, J. M. Fernandez-Diaz, and R. D. Crespo, Phys. Rev. E. 60, 45 (1999).

[16] Z. H. Li, H. P. Tian, T. Wang, and G. S. Zhou, Acta Opt. Sin. (in Chinese) 23, 289 (2003).

[17] K. Nakkeeran, Chaos, Soliton and Fractals 13, 673 (2002).

[18] A. Ankiewicz, K. Maruno, and N. Akhmediev, Phys. Lett. A 308, 397 (2003).

[19] V. E. Zakharov and A. B. Shabat, Soviet Phys. JETP 34, 62 (1972).

[20] Y. Chen and J. Atai, IEEE J. Quantum Electron. 34, 1301 (1998).