[1] [1] G. Berrettini, G. Meloni, L. Giorgi, F. Ponzini, F. Cavaliere, P. Ghiggino, L. Poti, and A. Bogoni, IEEE Photon. Technol. Lett. 21, 453 (2009).

[2] [2] A. Bogoni, IEEE J. Sel. Top. Quantum Electron. 17, 472 (2011).

[3] [3] E. T. Lopez, J. A. Lazaro, C. Arellano, V. Polo, and J. Prat, IEEE Photon. Technol. Lett. 22, 97 (2010).

[4] [4] S. Moon, H. Lee, and C. Lee, in Proceedings of CLEO'2011 CFH1 (2011).

[5] [5] H. Hu and H. Anis, IEEE J. Lightwave Technol. 26, 870 (2008).

[6] [6] P. Li , J. Xu, and L. Chen, in Proceedings of OECC'2011 15 (2001).

[7] [7] Q. Guo, A. V. Tran, and C. Chae, IEEE Photon. Technol. Lett. 23, 1442 (2011).

[8] [8] H. Kim, in Proceedings of OFC'2011 OMP8 (2011).

[9] [9] B. Schrenk, G. de Valicourt, M. Omella, J. A. Lazaro, R. Brenot, and J. Prat, IEEE Photon. Technol. Lett. 22, 392 (2010).

[10] [10] K. Y. Cho, J. H. Chang, B. S. Choi, Y. Takushima, and Y. C. Chung, in Proceedings of OFC'2011 OMP2 (2011).

[11] [11] B. Schrenk, G. de Valicourt, J. A. Lazaro, and J. Prat, in Proceedings of OFC'2011 JWA79 (2011).

[12] [12] J. Prat, C. Arellano, V. Polo, and J. Lazaro, in Proceedings of ECOC'2006 531 (2006).

[13] [13] C. W. Chow, G Talli, A. D. Ellis, and P. D. Townsend, Opt. Express 16, 1860 (2008).

[14] [14] T. T. Pham, H. Kim, Y. Won, and S. Han, in Proceedings of OFC'2009 OThA2 (2009).

[15] [15] L. Liu, M. Zhang, M. Liu, X. Zhang, and P. Ye, Chin. Opt. Lett. 9, 020606 (2011).

[16] [16] F. Xu, M. Khalighi, and S. Bourennane, J. Opt. Commun. Netw. 1, 404 (2009).

[17] [17] N. Azzam, M. H. Aly, and A. K. AbouiSeoud, in Proceedings of NRSC'2009 C10 (2009).