[1] Z. Jacob, L. V. Alekseyev, and E. Narimanov, Opt. Express 14, 8247 (2006).

[2] Z. Liu, H. Lee, Y. Xiong, C. Sun, and X. Zhang, Science 315, 1686 (2007).

[3] I. I. Smolyaninov, Y. J. Hung, and C. C. Davis, Science 315, 1699 (2007).

[4] H. Lee, Z. Liu, Y. Xiong, C. Sun, and X. Zhang, Opt. Express 15, 15886 (2007).

[5] J. Rho, Z. L. Ye, Y. Xiong, X. B. Yin, Z. Liu, H. Choi,G. Bartal, and X. Zhang, Nat. Commun. 1, 143 (2010).

[6] X. Zhang and Z. Liu, Nat. Mater. 7, 435 (2008).

[7] G. Zheng, R. Zhang, S. Li, P. He, and H. Zhou, Chin. Phys. B 20, 117802 (2011).

[8] G. Zheng, R. Zhang, S. Li, P. He, H, Zhou, and Y. Shi, IEEE Photon. Techol. Lett. 23, 1234 (2011).

[9] J. Zhao, G. Zheng, S. Li, H. Zhou, Y. Ma, R. Zhang, Y. Shi, and P. He, Chin. Opt. Lett. 10, 042302 (2012).

[10] A. Ourir, G. Lerosey, F. Lemoult, M. Fink, and J. de Rosny, Appl. Phys. Lett. 101, 111102 (2012).

[11] A. Sentenac, P. C. Chaumet, and K. Belkebir, Phys. Rev. Lett. 97, 243901 (2006).

[12] S. G. Aitken and A. D. Abell, Aust. J. Chem. 58, 3 (2005).

[13] C. O. Kappe and D. Dallinger, Nat. Rev. Drug Discov. 5, 51 (2006).

[14] F. Sterzer, IEEE Microw. Mag. 3, 65 (2002).

[15] S. C. Hagness, E. C. Fear, and A. Massa, IEEE Antenn. Wireless Propag. Lett. 11, 1592 (2012).

[16] M. Zhong, Chin. Opt. Lett. 11, 101601 (2013).

[17] B. Na, J. Shi, C. Guan, and Z. Wang, Chin. Opt. Lett. 11, 111602 (2013).

[18] Z. Jacob, L. V. Alekseyev, and E. Narimanov, J. Opt. Soc. Am. A. 24, 52 (2007).

[19] W. Zhang, H. Chen, and H. O. Moser, Appl. Phys. Lett. 98, 073501 (2011).

[20] B. Zheng, R. Zhang, M. Zhou, W. Zhang, S. Lin, Z. Ni, H. Wang, F. Yu, and H. Chen, Appl. Phys. Lett. 104, 073502 (2014).