Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

Helical topological edge states in a quadrupole phase

Liu, Feng, Deng, Hai-Yao and Wakabayashi, Katsunori 2019. Helical topological edge states in a quadrupole phase. Physical Review Letters 122 (8) , 086804. 10.1103/PhysRevLett.122.086804

[thumbnail of Deng et al 2018.pdf]
Preview
PDF - Published Version
Download (864kB) | Preview

Abstract

A topological electric quadrupole is a recently proposed concept that extends the theory of electric polarization of crystals to higher orders. Such a quadrupole phase supports topological states localized on both edges and corners. In this work, we show that in a quadrupole phase of a honeycomb lattice, topological helical edge states and pseudospin-polarized corner states appear by making use of a pseudospin degree of freedom related to point group symmetry. Furthermore, we argue that a general condition for the emergence of helical edge states in a (pseudo)spinful quadrupole phase is the existence of either mirror or time-reversal symmetry. Our results offer a way of generating topological helical edge states without spin-orbital couplings.

Item Type: Article
Date Type: Publication
Status: Published
Schools: Physics and Astronomy
Publisher: American Physical Society
ISSN: 0031-9007
Date of First Compliant Deposit: 20 January 2020
Last Modified: 30 Oct 2020 10:45
URI: https://orca.cardiff.ac.uk/id/eprint/128132

Citation Data

Cited 82 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item Edit Item

Downloads

Downloads per month over past year

View more statistics