Subwavelength light confinement and propagation: A numerical study of a two-layer silver film with perforated holes

Confinement and propagation of light under the diffraction limit is a substantial challenge for the development of waveguides as components in subwavelength optical devices. Light confinement and propagation at optical frequencies in a two-layer silver film with a periodic array of holes is investigated in a numerical study using the discrete dipole approximation method. Extraordinary subwavelength confinement and propagation of light can be obtained along an extremely subwavelength cross section of a region as small as 10 x 20 nm(2) at a distance of over 10 mu m. This study provides rational design of waveguides under subwavelength dimensions. (C) 2013 AIP Publishing LLC.