Higher-order topological solitonic insulators

TL;DR

This paper theoretically predicts higher-order topological insulator states in a magnetic soliton system on a breathing kagome lattice, demonstrating robust corner states and verifying predictions with micromagnetic simulations.

Contribution

It introduces a new magnetic soliton platform for higher-order topological insulators and provides a comprehensive phase diagram and robustness analysis.

Findings

Prediction of topologically protected corner states

Verification through micromagnetic simulations

Identification of phase transition conditions

Abstract

Pursuing topological phase and matter in a variety of systems is one central issue in current physical sciences and engineering. Motivated by the recent experimental observation of corner states in acoustic and photonic structures, we theoretically study the dipolar-coupled gyration motion of magnetic solitons on the two-dimensional breathing kagome lattice. We calculate the phase diagram and predict both the Tamm-Shockley edge modes and the second-order corner states when the ratio between alternate lattice constants is greater than a critical value. We show that the emerging corner states are topologically robust against both structure defects and moderate disorders. Micromagnetic simulations are implemented to verify the theoretical predictions with an excellent agreement. Our results pave the way for investigating higher-order topological insulators based on magnetic solitons.