1. B. Shine and J. Bautista, J. Lightwave Technol. 8, 140 (2000).
2. ZHANG Bao-ge, TAO Cai-xia and LU Yan, Journal of Optoelectronics Laser 21, 1641 (2010). (in Chinese)
3. H. P. Chan, Q. Wu, K. X. Chen, W. Y. Chan and B. P. Pal, International Photonics Global Conference (IPGC), Singapore, 2008.
4. K. Jinguji and M. Oguma, J. Lightwave Technol. 18, 252 (2000).
5. Lian-Wee Luo, Salah Ibrahim, Arthur Nitkowski, Zhi Ding, Carl B. Poitras, S. J. Ben Yoo and Michal Lipson, Opt. Express 18, 23079 (2010).