[1] Maier S A. IEEE Journal of Selected Topics in Quantum Electronics, 2006, 12(6): 1671.

[2] Dionne J A, Sweatlock L A, Atwater H A, et al. Physical Review B, 2006, 73(3): 035407.

[3] Aporvari M S, Aporvari A S, Kheirandish F. Applied Optics, 2016, 55(9): 2375.

[4] Liu L, Han Z, He S. Optics Express, 2005, 13(17): 6645.

[5] Pile D F P, Gramotnev D K. Optics Letters, 2004, 29(10): 1069.

[6] Moreno E, Rodrigo S G, Bozhevolnyi S I, et al. Physical Review Letters, 2008, 100(2): 023901.

[7] Boltasseva A, Volkov V S, Nielsen R B, et al. Optics Express, 2008, 16(8): 5252.

[8] Holmgaard T, Gosciniak J, Bozhevolnyi S I. Optics Express, 2010, 18(22): 23009.

[9] Zou C L, Sun F W, Xiao Y F, et al. Applied Physics Letters, 2010, 97(18): 183102.

[10] L Hong-bo, LIU Yu-min, YU Zhong-yuan, et al. Chinese Optics Letters, 2014, 12(11): 103.

[11] Bian Y, Zheng Z, Liu Y, et al. Optics Express, 2011, 19(23): 22417.

[12] Bian Y, Zheng Z, Zhao X, et al. Journal of Optics, 2013, 15(5): 055011.

[15] Huang M H, Mao S, Feick H, et al. Science, 2001, 292(5523): 1897.

[16] Zhang Q, Li G, Liu X, et al. Nature Communications, 2014, 5: 4953.

[17] Sharma A K, Gupta B D. Journal of Applied Physics, 2007, 101(9): 093111

[18] Mu J, Chen L, Li X, et al. Applied Physics Letters, 2013, 103(13): 131107.

[19] Jietao L, Binzong X, Jing Z, et al. Chinese Physics B, 2012, 21(10), 107303.