Manipulating reflection-type all-dielectric non-local metasurfaces via parity of particle number

TL;DR

This paper explores how the parity of particle number influences the reflection properties of non-local dielectric metasurfaces, revealing parity-dependent behaviors and potential for controlling light in photonic circuits.

Contribution

It introduces a novel approach to manipulate non-local metasurfaces using particle number parity, demonstrating its effects on reflectivity and transmission in finite and infinite structures.

Findings

Parity-dependent reflectivity divergence with non-local coupling

Achieving reflection and transmission reversals by alternating particle parity

High reflection linked to backward scattering and suppression of lateral scatterings

Abstract

Parity of particle number is a new degree of freedom for manipulating metasurface, while its influence on controlling non-local metasurfaces remains an unresolved and intriguing question. We propose a metasurface consisting of periodically arranged infinite-long cylinders made from multiple layers of SiO2 and WS2. The cylinder exhibits strong backward scattering due to the overlapping magnetic dipole and electric quadrupole resonances. Without non-local coupling in unit cells, the infinite-size metasurface manifests high reflection across all instances. However, parity-dependent reflectivity diverges with non-local coupling in supercells, exhibiting either increased logarithmic or decreased exponential behavior, with significant distinctions at small particle numbers. Interestingly, equal magnitude reflection and transmission reversals are achievable through alternation between adjacent odd and even particle numbers. The finite-size non-local metasurfaces behave similarly to the infinite-size counterparts, yet high reflection disappears at small particle numbers due to energy leakage. Essentially, high reflection arises from strong backward scattering and effective suppression of lateral multiple scatterings. Our work aids in the actual metasurface design and sheds new light on photonic integrated circuits and on-chip optical communication.