Portal de Periódicos da CAPES

Artigo Acesso aberto Produção Nacional Revisado por pares

BIBTEX RIS

Discovery of higher-order topological insulators using the spin Hall conductivity as a topology signature

2021; Nature Portfolio; Volume: 7; Issue: 1 Linguagem: Inglês

10.1038/s41524-021-00518-4

2057-3960

Marcio Costa, Gabriel R. Schleder, Carlos Mera Acosta, A. C. M. Padilha, Frank Cerasoli, Marco Buongiorno Nardelli, A. Fazzio,

Quantum and electron transport phenomena

Abstract The discovery and realization of topological insulators, a phase of matter which hosts metallic boundary states when the d -dimension insulating bulk is confined to ( d − 1)-dimensions, led to several potential applications. Recently, it was shown that protected topological states can manifest in ( d − 2)-dimensions, such as hinge and corner states for three- and two-dimensional systems, respectively. These nontrivial materials are named higher-order topological insulators (HOTIs). Here we show a connection between spin Hall effect and HOTIs using a combination of ab initio calculations and tight-binding modeling. The model demonstrates how a non-zero bulk midgap spin Hall conductivity (SHC) emerges within the HOTI phase. Following this, we performed high-throughput density functional theory calculations to find unknown HOTIs, using the SHC as a criterion. We calculated the SHC of 693 insulators resulting in seven stable two-dimensional HOTIs. Our work guides novel experimental and theoretical advances towards higher-order topological insulator realization and applications.