Title :
Enhanced Focusing Properties Using Surface Plasmon Multilayer Gratings
Author :
Li, Hui ; Yan, Lianshan ; Guo, Zhen ; Pan, Wei ; Wen, Kunhua ; Li, Hengyi ; Luo, Xiangang
Author_Institution :
Center for Inf. Photonics & Commun., Southwest Jiaotong Univ., Chengdu, China
Abstract :
A subwavelength slit with metal-dielectric-metal (MDM) composite surface gratings is proposed and numerically investigated using finite-difference time-domain (FDTD) method. Compared with conventional monometal-grating based structures, focusing properties of the proposed MDM structure can be enhanced based on multiple scattering and coupling of surface plasmon polaritons (SPPs) along the metal/dielectric multilayer films, especially the focal length can be varied from ~ 2.6 to 5.82 μm by adjusting the dielectric thickness.
Keywords :
diffraction gratings; finite difference time-domain analysis; optical focusing; optical multilayers; polaritons; surface plasmons; enhanced focusing; finite difference time-domain method; focal length; metal-dielectric multilayer films; metal-dielectric-metal composite surface gratings; subwavelength slit; surface plasmon multilayer gratings; surface plasmon polaritons; Dielectrics; Films; Focusing; Gratings; Metals; Surface waves; Gratings; multilayer interference coatings; plasmonics; subwavelength structures;
Journal_Title :
Photonics Journal, IEEE
DOI :
10.1109/JPHOT.2011.2178591
