Estudio teórico y numérico de la difracción en óptica electromagnética. VII. Resonancias en la transmisión por una rendija en el régimen de sublongitud de onda

Abstract

Using a rigorous theory we study the diffraction of TM-polarized plane waves by a slit of width $l$ in a screen of infinite conductivity and thickness $h$. We have determined the resonances that appear when the incident wavelength is bigger than the slit width (subwavelength regime). We analyze numerically the transmission coefficient and the normally diffracted energy as functions of the incident wavelength, the screen thickness, and the slit width. We have found that both quantities present high anomalous values (resonances) for certain incident wavelengths radiation. Also, we show numerically that there are linear relationships between the resonant amplitudes and the optogeometrical parameters of the system, as well as among the same resonant magnitudes.