Higher-order topological insulator with glide reflection symmetry

TL;DR

This paper introduces a coupled BBH model with glide reflection symmetry, revealing new topological phases, phase transitions, and protected band crossings, expanding understanding of higher-order topological insulators with nonsymmorphic symmetries.

Contribution

It proposes a novel coupled BBH model with glide reflection symmetry, demonstrating new topological phenomena and phase transitions beyond traditional models.

Findings

Prediction of a topological phase transition to a semimetal

Identification of glide symmetry-protected band crossings

Demonstration of interplay between higher-order topology and nonsymmorphic symmetry

Abstract

The Benalcazar-Bernevig-Hughes(BBH) model is one of the most representative higher-order topological insulators with different bulk-edge correspondence comparing conventional topological states. In this work, we propose to realize a couple-BBH model with glide reflection symmetry by coupling two topologically distinct BBH models. Such a system gives rise to intriguing properties beyond the traditional BBH model. A topological phase transition from higher-order topological phase to a semimetal has been predicted in this system. Furthermore, the band crossing points and nodal ring protected by glide reflection symmetry has also been explored. Our work provides a viewpoint to demonstrate the versatile phenomena induced by the interplay between higher-order topology and nonsymmorphic symmetries.