Fluorescence transmission through metal films with one-dimensional corrugation was demonstrated in a series of elegant experiments by Hall [1, 2], where light transmission is attributed to the excitation of surface plasmon modes in the metal, which subsequently couple back into transverse radiation through interaction with the grating. More recently, Ebbesen and co-workers reported enhanced light transmission through metal films modulated with a 2-D array of subwavelength apertures , which sparked considerable experimental and theoretical activity in the phenomenon . The presence of open apertures within the films results in stronger coupling between the two sides. We demonstrate that the transmission of light through 1-D corrugated metal films is inherently a 2-D coherent scattering phenomenon, even when the light source is incoherent. In films consisting of two-dimensional arrays of sub-wavelength apertures, an additional mechanism exists in the direct transmission of light through the apertures, which is the dominant mechanism of transmission.
© 2004 Optical Society of AmericaPDF Article