[1] J. H. Song, J. H. Song, K.-Y. Kim, J. Cho, D. Han, J. Lee, Y. S. Lee, S. Jung,Y. Oh, D.-H. Jang, and K. S. Lee, IEEE Photon. Technol. Lett. 17, 1668 (2005).
[2] M. Fuller, Lightwave 21, 24 (2004).
[3] J. Li, J. An, Y. Wu, J. Li, H. Wang, and X. Hu, Chin. Opt. Lett. 8, 060588 (2010).
[4] X. Lin, T. Lang, and J. He, J. Lightwave Technol. 29, 1407 (2011).
[5] C. L. Xu, X. Hong, and W. Huang, Opt. Express 14, 4675 (2006).
[6] J. Song and J. F. Ding, Electron. Lett. 46, 1213 (2010).
[7] ITU-T G.983.3, "A broadband optical access system with increased service capability by wavelength allocation".
[8] H. Ren, J. Ma, W. Wen, Y. Qin, Z. Wu, W. Hu, C. Jiang, and Y. Jin, Chin. Opt. Lett. 9, 042501 (2011).
[9] W. Bogaerts, S. K. Selvaraja, P. Dumon, J.Brouckaert, K. De Vos, D. Van Thourhout, and R. Baets, J. Sel. Top. Quantum Electron. 16, 33 (2010).
[10] Z. Zhou, Z. Tu, B. Yin, W. Tan, L. Yu, H. Yi, and X. Wang, Chin. Opt. Lett. 11, 012501 (2013).
[11] Y. Shi, S. Anand, and S. He, J. Lightwave Technol. 27, 1443 (2009).
[12] H. Rao, R. Scarmozzino, and R. M. Osgood, Jr., IEEE Photon. Technol. Lett. 11, 830 (1999).
[13] J. Zhou, H. Shen, R. Jia, H. Liu, Y. Tang, C. Yang, C. Xue, and X. Liu, Chin. Opt. Lett. 9, 082303 (2011).
[14] Y. Shi, D. Dai, and S. He, Opt. Commun. 253, 276 (2005).
