Non-Abelian topological edge states in a one-dimensional ladder system with flat bands
Phys. Rev. B 113, 155409 – Published 6 April, 2026
DOI: https://doi.org/10.1103/bq31-trs1
Abstract
Non-Abelian topological theory enables the classification of multigap systems and captures complex structures beyond conventional band topology. In this study, we propose a four-band non-Abelian topological insulator model in the one-dimensional ladder lattice. This model features a pair of flat bands and supports diverse edge states tunable via system parameters. More importantly, the realization in such low-complexity systems enlarges the application potential of the non-Abelian topological theory. To demonstrate this, we design a topolectrical circuit simulation scheme, laying a direct theoretical foundation for the experimental verification of non-Abelian topological insulators. Both the theoretical analysis and the simulation scheme show that the flat-band system establishes a practical, accessible platform that directly facilitates the realization and future application of non-Abelian topological phases.