Extraordinary Transmission Through Slit Arrays In Metal Films

Extraordinary transmission of electromagnetic wave through an array of subwavelength slits in a metal film is considered. Probable mechanisms responsible for this effect are analyzed. Comparison of theoretical model, semi‐analytical model based on Fabry‐Perot formula and results of numerical simulation of Maxwell equations in time‐dependent form for silver with various geometric parameters is presented.

It is concluded from numerical results the validity of single‐mode approximation described by Fabry‐Perot formula. All characteristics of extraordinary transmission are completely described by single‐mode approximation. Surface plasmon coupling with propagative eigenmode of slit leads to zero in transmittance for certain wavelength, i.e. plays negative role in extraordinary transmission.