Spatial symmetries in nonlocal multipolar metasurfaces  

作　　者：Karim Achouri Ville Tiukuvaara Olivier J.F.Martin 

机构地区：[1]Institute of Electrical and Microengineering,École Polytechnique Fédérale de Lausanne,Nanophotonics and Metrology Laboratory,Lausanne,Switzerland

出　　处：《Advanced Photonics》2023年第4期9-22,共14页先进光子学（英文）

基　　金：We gratefully acknowledge funding from the Swiss National Science Foundation(Grant No.PZ00P2-193221).

摘　　要：We propose a framework that connects the spatial symmetries of a metasurface to its material parameter tensors and its scattering matrix.This provides a simple and universal way to effortlessly determine the properties of a metasurface scattering response,such as chirality or asymmetric transmission,and which of its effective material parameters should be taken into account in the prospect of a homogenization procedure.In contrast to existing techniques,this approach does not require any a priori knowledge of group theory or complicated numerical simulation schemes,hence making it fast,easy to use and accessible.Its working principle consists in recursively solving symmetry-invariance conditions that apply to dipolar and quadrupolar material parameters,which include nonlocal interactions,as well as the metasurface scattering matrix.The overall process thus only requires listing the spatial symmetries of the metasurface.Using the proposed framework,we demonstrate the existence of multipolar extrinsic chirality,which is a form of chiral response that is achieved in geometrically achiral structures sensitive to field gradients,even at normal incidence.

关 键 词：spatial symmetries METAMATERIALS bianisotropy MULTIPOLES CHIRALITY 

分 类 号：O431.1[机械工程—光学工程]