On the transmission of light through a single rectangular hole

TL;DR

This paper demonstrates that a single rectangular hole in a metal film exhibits resonant light transmission near its cutoff wavelength, with potential applications in spectroscopy and nonlinear optics.

Contribution

It reveals the resonance behavior of rectangular holes and quantifies the transmittance dependence on geometry and dielectric properties, highlighting field enhancement effects.

Findings

Transmission resonances occur near the cutoff wavelength.

Normalized transmittance depends on hole dimensions and dielectric constant.

Significant electric field enhancement at hole interfaces.

Abstract

In this Letter we show that a single rectangular hole exhibits transmission resonances that appear near the cutoff wavelength of the hole waveguide. For light polarized with the electric field pointing along the short axis, it is shown that the normalized-to-area transmittance at resonance is proportional to the ratio between the long and short sides, and to the dielectric constant inside the hole. Importantly, this resonant transmission process is accompanied by a huge enhancement of the electric field at both entrance and exit interfaces of the hole. These findings open the possibility of using rectangular holes for spectroscopic purposes or for exploring non-linear effects.