An angle-independent Frequency Selective Surface in the optical range

Abstract

We suggest and numerically demonstrate a design for Frequency Selective Surfaces (FSS) operating in the optical (visible and near-infrared) range. The position and width of the FSS bandpass do not depend on the angle of incidence and polarization state of the incoming light, allowing high transmission at any angle. The FSS is formed by annular apertures perforated in a metal film and arranged in a square array. Angle- and polarization-independent transmission properties are demonstrated for silver. These results can be extended to other metals as well as to other frequency domains.

Square-shaped metal screens in the infrared to terahertz spectral region: Resonance frequency, band gap, and bandpass filter characteristics

“…1͒. To a limited extent, other recent investigations also found split transmission features [22][23][24] without fully considering its polarization aspect, or correlating the appearance with the nature of the beam incident on the sample in the spectrometer used. A similar feature at / g Ͼ 1 has been observed in the past on screen 500, 17 and was assigned to Wood's anomaly.…”

Increasing the bandwidth of coaxial aperture arrays in radar frequencies

“…[2], an array of square coaxial cavities in a slab of silver is presented. At optical wavelengths, silver is not a perfectly conducting metal: the skin depth is not negligible and virtually enlarges the cavity (cf.…”

“…Refs. [2] and [5]) are the Fabry-Pérot-like resonances due to coaxial waveguide modes. They can be identified by plotting the fields in the cavities or the (equivalent) currents on the interfaces of the model.…”

“…[2]: an array of square coaxial cavities made in a silver slab. The properties are stable with the angle of incidence and relatively similar for both polarizations.…”

Optical metasurfaces with robust angular response on flexible substrates

“…13 FSSs are typically composed of periodic metallic inclusions or apertures on a metallic sheet with subwavelength periodicity, which provides a bulk response analogous to an averaged impedance boundary. Recently, FSS structures have been designed in the visible range, providing a response independent on the angles of incidence, 14 consistent with the averaged description of such arrays. 12,15 In this paper, we experimentally verify the angular independence of the optical response of plasmonic metasurfaces and apply them to the flexible substrate technology, recently developed in Ref.…”