[1] M. Asghari, I. H. White, and R. V. Penty, J. Lightwave Technol. 15, 1181 (1997).
[2] S. L. Danielsen, P. B. Hansen, K. E. Stubkjaer, M. Schilling, K. Wunstel, W. Idler, P. Doussiere, and F. Pommerau, IEEE Photon. Technol. Lett. 10, 60 (1998).
[3] T. Durhuus, B. Mikkelsen, C. Joergensen, S. L. Danielsen, and K. E. Studkjaer, J. Lightwave Technol. 14, 942 (1996).
[4] V. M. Menon, W. Tong, C. Q. Li, F. Xia, I. Glesk, P. R. Prucnal, and S. R. Forrest, in Proceedings of the 15th Annual Meeting of the LEOS 49 (2002).
[5] J. M. Tang, P. S. Spencer, and K. A. Shore, J. Lightwave Technol. 16, 86 (1998).
[6] C. Xie and P. Ye, Chin. J. Lasers (in Chinese) 27, 525 (2000).
[7] Y. Zhang and P. Ye, Acta Opt. Sin. (in Chinese) 22, 99 (2002).
