Experimental observation of non-Abelian topological charges and bulk-edge correspondence

TL;DR

This paper reports the first experimental observation of non-Abelian topological charges in a PT-symmetric system, revealing a new form of bulk-edge correspondence and advancing the understanding of non-Abelian topological phases.

Contribution

It provides the first experimental evidence of non-Abelian topological charges and introduces the concept of non-Abelian bulk-edge correspondence in topological matter.

Findings

Experimental observation of non-Abelian topological charges.

Identification of non-Abelian bulk-edge correspondence.

Potential implications for quantum computation and topological phase manipulation.

Abstract

In the past decades, topological concepts have emerged to classify matter states beyond the Ginzburg-Landau symmetry breaking paradigm. The underlying global invariants are usually characterized by integers, such as Chern or winding numbers. Very recently, band topology characterized by non-Abelian topological charges has been proposed, which possess non-commutative and fruitful braiding structures with multiple (>1) bandgaps entangled together. Despite many potential exquisite applications including quantum computations, no experimental observation of non-Abelian topological charges has been reported. Here, we experimentally observe the non-Abelian topological charges in a PT (parity and time-reversal) symmetric system. More importantly, we propose non-Abelian bulk-edge correspondence, where edge states are found to be described by non-Abelian charges. Our work opens the door towards non-Abelian topological phase characterization and manipulation.