Bulk-edge correspondence and long-range hopping in the topological plasmonic chain

Nanophotonics

article

Simon R. Pocock¹  Paloma A. Huidobro¹  Vincenzo Giannini¹ 

[1] Physics Department, Blackett Laboratory, Imperial College London;Instituto de Telecomunicações, Insituto Superior Tecnico-University of Lisbon;Instituto de Estructura de la Materia (IEM-CSIC)

关键词: topological photonics;    bulk-edge correspondence;    topological plasmonics;   

DOI  :  10.1515/nanoph-2019-0033

学科分类：社会科学、人文和艺术（综合）

来源: De Gruyter

【 摘 要 】

The existence of topologically protected edge modes is often cited as a highly desirable trait of topological insulators. However, these edge states are not always present. A realistic physical treatment of long-range hopping in a one-dimensional dipolar system can break the symmetry that protects the edge modes without affecting the bulk topological number, leading to a breakdown in bulk-edge correspondence (BEC). Hence, it is important to gain a better understanding of where and how this occurs, as well as how to measure it. Here we examine the behaviour of the bulk and edge modes in a dimerised chain of metallic nanoparticles and in a simpler non-Hermitian next-nearest-neighbour model to provide some insights into the phenomena of bulk-edge breakdown. We construct BEC phase diagrams for the simpler case and use these ideas to devise a measure of symmetry-breaking for the plasmonic system based on its bulk properties. This provides a parameter regime in which BEC is preserved in the topological plasmonic chain, as well as a framework for assessing this phenomenon in other systems.

【 授权许可】

CC BY