[1] [1] M. J. Gander, R. McBride, J. D. C. Jones, D. Mogilevtsev, T. A. Birks, J. C. Knight, and P. St. J. Russell, Electron. Lett. 35, 63 (1999).

[2] [2] T.-L. Wu and C.-H. Chao, IEEE Photon. Technol. Lett. 17, (2005).

[3] [3] K. Saitoh and M. Koshiba, Opt. Express 12, 2027 (2004).

[4] [4] W. H. Reeves, J. C. Knight, P. St. J. Russell, and P. J. Roberts, Opt. Express 10, 609 (2002).

[5] [5] K. Saitoh, M. Koshiba, T. Hasegawa, and E. Sasaoka, Opt. Express 11, 843 (2003).

[6] [6] X. Z. Sheng and S. Q. Lou, Chin. Phys. Lett. 22, 2588 (2005).

[7] [7] N. L. Boling, A. J. Glass, and A. Owyoung, IEEE J. Quantum Electron. 14, 601 (1978).

[8] [8] Y. L. Hoo, W. Jin, J. Ju, H. L. Ho, and D. N. Wang, Opt. Commun. 242, 327 (2004).

[9] [9] K. Nakajima and M. Ohashi, IEEE Photon. Technol. Lett. 14, 492 (2002).

[10] [10] D. Ferrarini, L. Vincetti, M. Zoboli, A. Cucinotta, F. Poli, and S. Selleri, in Proceedings of OFC2003 2, 699 (2003).

[11] [11] Q. Wang, B. Yang, L. Zhang, H. Zhang, and L. He, Chin. Opt. Lett. 5, 538 (2007).

[12] [12] J. Liu, L. Xue, G. Kai, and X. Dong, Chin. Opt. Lett. 5, S214 (2007).