[1] [1] H A Bethe. Theory of diffraction by small holes [J]. Phys Rev, 1944, 66(7): 163-182.

[2] [2] F J Garcia-Vidala, L. Martin-Moreno, H J Lezec, et al.. Focusing light with a single subwavelength aperture flanked by surface corrugations [J]. Appl Phys Lett, 2003, 83(22): 4500-4502.

[3] [3] Xiebin Fan, Guo Ping Wang. Nanoscale metal waveguide arrays as plasmon lenses [J]. Opt Lett, 2006, 31(9): 1322-1324.

[4] [4] W M Saj. Light focusing on a stack of metal-in sulator-metal waveguides sharp edge [J] . Opt Express, 2009, 17(16): 13615-13623.

[5] [5] Dawoon Choi, Lim Yongjun, Roh Sookyoung, et al.. Optical beam focusing with a metal slit array arranged along a semicircular surface and its optimization with a genetic algorithm [J]. Appl Opt, 2010, 49(7): A30-A34.

[6] [6] I P Kaminow, W L Mammel, H P Weber. Metal clad optical waveguides: analytical and experimental study [J]. Appl Opt, 1974, 13(2): 396-405.

[7] [7] Wang Bing, Wang Guoping. Plasmon Bragg reflectors and nanocavities on flat metallicsurfaces [J]. Appl Phys Lett, 2005, 87(1): 013107.

[8] [8] Asanka Pannipitiya, Ivan D Rukhlenko, Malin Premaratne, et al.. Improved transmission model for metal-dielectric-metal plasmonic waveguides with stub structure [J] . Opt Experess, 2010, 18(6): 6191-6204.

[9] [9] E N Economou. Surface plasmons in thin films [J]. Phys Rev, 1969, 182(2): 539-554.

[10] [10] Dong Hongcheng, Liu Yang, Yi Kui, et al.. Theory analysis of polarized beam coherent combination [J]. Chinese J Lasers, 2009, 36(9): 2346-2351.

[11] [11] Yang Yisu, Huang Yongqing, Huang Hui, et al.. Design of photodetector with subwavelength grating structure [J] . Chinese J Lasers, 2009, 36(9): 2352-2357.

[12] [12] Wang Jingquan, Fang Liang, Zhang Zhiyou, et al.. Implementation of coherent array beam combination using twodimensional sine phase grating [J]. Chinese J Lasers, 2008, 35(1): 39-43.

[13] [13] Wang Hui, Zeng Wei, Song Guofeng. Simulation and development of subwavelength periodic hole array on Au film [J]. Acta Optica Sinica, 2009, 29(6): 1638-1643.