Light funneling mechanism explained by magneto-electric interference

Abstract

We investigate the mechanisms involved in the funneling of the optical energy into sub-wavelength grooves etched on a metallic surface. The key phenomenon is unveiled thanks to the decomposition of the electromagnetic field into its propagative and evanescent parts. We unambiguously show that the funneling is not due to plasmonic waves flowing toward the grooves, but rather to the magneto-electric interference of the incident wave with the evanescent field, this field being mainly due to the resonant wave escaping from the groove.

4 pages, 5 figures v3, added EPAPS

References in corpus (2)

• Transmission resonances on metallic gratings with very narrow slits
• Strong Discontinuities in the Complex Photonic Band Structure of Transmission Metallic Gratings

Cited by in corpus (5)

• Anomalous light absorption around subwavelength apertures in metal films
• Influence of spatial dispersion in metals on the optical response of deeply subwavelength slit arrays
• Plasmonic sensors based on funneling light through nanophotonic structures
• Lorentz-invariant topological structures of the electromagnetic field in a Fabry-Perot resonant slit-grating
• Universal metamaterial absorbe