Wavevector Selective Metasurfaces and Tunnel Vision Filters

TL;DR

This paper introduces wavevector selective metasurfaces that act as tunnel vision filters, allowing transmission only within specific light propagation directions, with potential applications in imaging, communication, and camouflage.

Contribution

The paper presents the first experimental demonstration of wavevector selective metasurfaces functioning as directional filters in the THz domain.

Findings

Metasurfaces can be engineered to be transparent only within narrow propagation angles.

Experimental validation of wavevector selectivity in the THz frequency range.

Potential applications include wavefront control, imaging, and stealth technologies.

Abstract

Metasurfaces offer unprecedented flexibility in the design and control of light propagation, replacing bulk optical components and exhibiting exotic optical effects. One of the basic properties of the metasurfaces, which renders them as frequency selective surfaces, is the ability to transmit or reflect radiation within a narrow spectral band that can be engineered on demand. Here we introduce and demonstrate experimentally in the THz domain the concept of wavevector selective surfaces -- metasurfaces transparent only within a narrow range of light propagation directions operating effectively as tunnel vision filters. Practical implementations of the new concept include applications in wavefront manipulation, observational instruments, vision and free-space communication in light-scattering environments, as well as passive camouflage.