[1] [1] R. Y. Chiao and A. M. Steinberg, Progress in Optics 37, 345 (1997).

[2] [2] R. W. Boyd and D. J. Gauthier, Process in Optics 43, 497 (2002).

[3] [3] D. Budker, D. F. Kimball, S. M. Rochester, and V. V. Yashchuk, Phys. Rev. Lett. 83, 1767 (1999).

[4] [4] M. M. Kash, V. A. Sautenkov, A. S. Zibrov, L. Hollberg, G. R. Welch, M. D. Lukin, Y. Rostovtsev, E. S. Fry, and M. O. Scully, Phys. Rev. Lett. 82, 5229 (1999).

[5] [5] Y. Aharonov, B. Reznik, and A. Stern, Phys. Rev. Lett. 81, 2190 (1998).

[6] [6] A. Kuzmich, A. Dogariu, L. J. Wang, P. W. Milonni, and R. Y. Chiao, Phys. Rev. Lett. 86, 3925 (2001).

[7] [7] G. S. Agarwal, T. N. Dey, and S. Menon, Phys. Rev. A 64, 053809 (2001).

[8] [8] D. Bortman-Arbiv, A. D. Wilson-Gordon, and H. Friedmann, Phys. Rev. A 63, 043818 (2001).

[9] [9] A. Dogariu, A. Kuzmich, and L. J. Wang, Phys. Rev. A 63, 053806 (2001).

[10] [10] S.-Y. Zhu and L.-G. Wang, Chin. Opt. Lett. 1, 47 (2003).

[11] [11] L.-G. Wang, N.-H. Liu, Q. Lin, and S.-Y. Zhu, Phys. Rev. E 68, 066606 (2003).

[12] [12] H. Kang, G. Hernandez, and Y. Zhu, Phys. Rev. A 70, 011801 (2004).

[13] [13] M. Sahrai, H. Tajalli, K. T. Kapale, and M. S. Zubairy, Phys. Rev. A 70, 023813 (2004).

[14] [14] E. Paspalakis, S.-Q. Gong, and P. L. Knight, Opt. Commun. 152, 293 (1998).

[15] [15] S.-Q. Gong, Y. Li, S.-D. Du, and Z.-Z. Xu, Phys. Lett. A 259, 43 (1999).

[16] [16] J.-H. Wu and J.-Y. Gao, Phys. Rev. A 65, 063807 (2002).

[17] [17] H.-M. Ma, S.-Q. Gong, C.-P. Liu, Z.-R. Sun, and Z.-Z. Xu, Opt. Commun. 223, 97 (2003).

[18] [18] C.-P. Liu, S.-Q. Gong, X.-J. Fan, and Z.-Z. Xu, Opt. Commun. 239, 383(2004).

[19] [19] J. Li, C. Liu, N. Cui, H. Li, and X. Fan, Chin. Opt. Lett. 2, 725 (2004).

[20] [20] J. Qian, C. Liu, and S. Gong, Chin. Opt. Lett. 3, 308 (2005).

[21] [21] X. J. Fan, J. J. Li, S. F. Tian, N. Cui, H. Li, A. Y. Li, and Z. Z. Xu, J. Modern Opt. 52, 1757 (2005).