[1] [1] J. B. Pendry, D. Schuring, and D. R. Smith, Science 312, 1780 (2006).

[2] [2] S. A. Cummer, B. I. Popa, D. Schuring, D. R. Smith, and J. B. Pendry, Phys. Rev. E. 74, 036621 (2006).

[3] [3] D. Schurig, J. J. Mock, B. J. Justice, S. A. Cummer, J. B. Pendry, A. F. Starr, and D. R. Smith, Science 314, 977 (2006).

[4] [4] M. Yan, Z. Ruan, and M. Qiu, Opt. Express 15, 17772 (2007).

[5] [5] W. Cai, U. K. Chettiar, A. V. Kildishev, V. M. Shalaev, and G. W. Milton, Appl. Phys. Lett. 91, 111105 (2007).

[6] [6] W. Yan, M. Yan, Z. Ruan, and M. Qiu, New J. Phys. 10, 043040 (2008).

[7] [7] Q. Wu, K. Zhang, F. Y. Meng, and L. W. Li, J. Phys. D: Appl. Phys. 42, 035408 (2009).

[8] [8] W. X. Jiang, J. Y. Chin, Z. Li, Q. Cheng, R. Liu, and T. J. Cui, Phys. Rev. E. 77, 066607 (2008).

[9] [9] Y. Lai, H Chen, Z. Q. Zhang, and C. T. Chan, Phys. Rev. Lett. 102, 093901 (2009).

[10] [10] Y. Lai, J. Ng, H. Y. Chen, D. Z. Han, J. J. Xiao, Z. Q. Zhang, and C. T. Chan, Phys. Rev. Lett. 102, 253902 (2009).

[11] [11] T. Li, M. Huang, J. Yang, Y. Yao, and J. Yu, Opt. Mater. Express 1, 911 (2011).

[12] [12] L. Lin, W. Wang, C. L. Du, and X. G. Luo, Opt. Express 16, 6809 (2008).

[13] [13] T. Yang, H. Chen, X. Luo, and H. Ma, Opt. Express 16, 18545 (2009).

[14] [14] W. X. Jiang and T. J. Cui, Opt. Express 18, 5121(2010).

[15] [15] T. H. Li, M. Huang, J. J. Yang, J. Yu, and Y. Z. Lan, J. Phys. D: Appl. Phys. 44, 325102 (2011).

[16] [16] Z. Chen, L. Wang, C. Wang, and Z. Fang, Chin. Opt. Lett. 9, 021601 (2011).

[17] [17] B. Kante, D. Germain, and A. Lustrac, Phys. Rev. B 80, 201104 (2009).

[18] [18] J. J. Zhang, H. S. Chen, L. X. Ran, Y. Luo, B. I. Wu, and J. A. Kong, Appl. Phys. Lett. 92, 084108 (2008).

[19] [19] Q. Du, J. Liu, and H. Yang, Chin. Opt. Lett. 9, 110015 (2011).

[20] [20] C. Caloz, Mater. Today 12, 12 (2009).