Mode analysis of surface plasmon metal-dielectric-metal nanowire array waveguide at sub-wavelength scale Jinping Tian, Xijing Liang, Caijiao Zhang and Hongjuan Li Eur. Phys. J. D, 67 5 (2013) 103 Published online: 07 May 2013 DOI: 10.1140/epjd/e2013-40018-5