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arXiv · 2611.07456

Probing Non-Abelian Topology through Quench Dynamics

Abstract

Quench dynamics offer valuable insights to topological matter, wherein the emergent topological phenomena serve as a dynamic probe to the topology of static Hamiltonians. While such a practice has been widely applied to detect the Abelian band topology or the Euler-class topology of band nodes, little is known regarding the quench dynamics of non-Abelian topological insulators in multiband systems, where the intertwining geometry of all eigenstates necessitates the description of noncommutative topological charges. Here we propose a quench protocol for non-Abelian topological insulators, so that the underlying topology can be systematically probed using dynamic signatures. Specifically, we develop a band-projection scheme to extract the gap-resolved topology from dynamic skyrmions in the emergent quasimomentum--time manifolds of the quench processes. These skyrmions are characterized by a series of gap-resolved dynamic Chern numbers, which enable us to reconstruct the full non-Abelian topology of the post-quench Hamiltonian, including the global non-Abelian topological charge and edge-state patterns under the open-boundary condition. Our proposal offers dynamical access to non-Abelian topology in multiband systems, and can be readily implemented using photons or cold atoms.

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Zhenming Zhang, Tianyu Li, Wei Yi. 2026-11-05. Probing Non-Abelian Topology through Quench Dynamics. https://arxiv.org/abs/2611.07456

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