[1] [1] Q. Lin, O. J. Painter, and G. P. Agrawal, Opt. Express 15, 16604 (2007).

[2] [2] D. Dai and J. E. Bowers, Opt. Express 19, 10940 (2011).

[3] [3] M. A. Foster1, A. C. Turner, M. Lipson, and A. L. Gaeta, Opt. Express 16, 1300 (2008).

[4] [4] K. Liu, W. Xu, Z. Zhu, W. Ye, X. Yuan, and C. Zeng, Opt. Lett. 37, 2826 (2012).

[5] [5] J. Zhang, Q. Lin, G. Piredda, R. W. Boyd, G. P. Agrawal, and P. M. Fauchet, Opt. Express 15, 7682 (2007).

[6] [6] L. H. Yin, Q. Lin, and G. P. Agrawal, Opt. Lett. 31, 1295 (2006).

[7] [7] S. C. V. Latas and M. F. S. Ferreira, Opt. Lett. 35, 1071 (2010).

[8] [8] R. Hao, L. Li, R. Yang, Z. Li, and G. Zhou, Chin. Opt. Lett. 3, 030136 (2005).

[9] [9] W. H. Renninger, A. Chong, and F. W. Wise, Opt. Lett. 33, 3025 (2008).

[10] [10] X. Zeng, H. Guo, B. Zhou, and M. Bache, Opt. Express 20, 27072 (2012).

[11] [11] M. A. Foster and A. L. Gaeta, Opt. Express 13, 6848 (2005).

[12] [12] L. H. Yin, Q. Lin, and G. P. Agrawal, Opt. Lett. 32, 391 (2007).

[13] [13] E. J. R. Kelleher, M. Erkintalo, and J. C. Travers, Opt. Lett. 37, 5217 (2012).

[14] [14] P. Grelul and N. Akhmediev, Nat. Photon. 6, 84 (2012).

[15] [15] L. M. Mandeng and C. Tchawoua, J. Opt. Soc. Am. B 30, 1382 (2013).

[16] [16] W. Ding, A. V. Gorbach, W. J. Wadsworth, J. C. Knight, D. V. Skryabin, M. J. Strain, M. Sorel, and R. M. De La Rue, Opt. Express 18, 26625 (2010).

[17] [17] N. Kejalakshmy, A. Agrawal, Y. Aden, D. M. H. Leung, B. M. A. Rahman, and K. T. V. Grattan, Appl. Opt. 49, 3173 (2010).

[18] [18] A. D. Bristow, N. Rotenberg, and H. M. van Drielb, Appl. Phys. Lett. 90, 191104 (2007).

[19] [19] L. H. Yin and G. P. Agrawal, Opt. Lett. 32, 2031 (2007).