Transmission magnitude and phase control for polarization-preserving reflectionless metasurfaces

TL;DR

This paper demonstrates a new metasurface design that achieves reflectionless, full-phase control of transmission for electromagnetic waves, applicable across microwave and optical frequencies, even with lossy materials.

Contribution

It introduces a novel meta-atom configuration enabling complete phase coverage and reflectionless transmission under oblique TM illumination, expanding metasurface capabilities.

Findings

Achieves 2π transmission phase coverage with reflectionless transmission.

Maintains full phase control even with lossy metasurfaces.

Provides numerical examples in microwave and optical regimes.

Abstract

For transmissive applications of electromagnetic metasurfaces, an array of subwavelength Huygens' metaatoms are typically used to eliminate reflection and achieve a high transmission power efficiency together with a wide transmission phase coverage. We show that the underlying principle of low reflection and full control over transmission is asymmetric scattering into the specular reflection and transmission directions that results from a superposition of symmetric and anti-symmetric scattering components, with Huygens' meta-atoms being one example configuration. Available for oblique illumination in TM polarization, a meta-atom configuration comprising normal and tangential electric polarizations is presented, which is capable of reflectionless, fullpower transmission and a $2\pi$ transmission phase coverage as well as full absorption. For lossy metasurfaces, we show that a complete phase coverage is still available for reflectionless designs for any value of absorptance. Numerical examples in the microwave and optical regimes are provided.