Related papers: Breakdown of Non-Bloch Bulk-Boundary Correspondence and Emergent Topology in Floquet Non-Hermitian Systems

Breakdown of Non-Bloch Bulk-Boundary Correspondence and Emergent Topology in Floquet Non-Hermitian Systems

URL: http://arxiv.org/abs/2510.09193v1
Date: Fri, 10 Oct 2025 09:36:17 GMT
Title: Breakdown of Non-Bloch Bulk-Boundary Correspondence and Emergent Topology in Floquet Non-Hermitian Systems
Authors: Hong Wu, Xue-Min Yang, Hui Liu,
Abstract summary: Topological edge states in gaps of non-Hermitian systems are robust due to topological protection.<n>We show that edge states may be suppressed by infinitesimal perturbations that preserve sublattice symmetry.<n>Our results provide a promising new avenue for exploring novel non-Hermitian topological phases.
Score: 7.898474960620258
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Abstract: Topological edge states in gaps of non-Hermitian systems are robust due to topological protection. Using the non-Hermitian Floquet Su-Schrieffer-Heeger model, we show that this robustness can break down: edge states may be suppressed by infinitesimal perturbations that preserve sublattice symmetry. We identify this fragility to the instability of the quasienergy spectrum in finite-size systems, leading to a breakdown of the non-Bloch bulk-boundary correspondence defined on the generalized Brillouin zone. To resolve this, we establish a correspondence between the number of stable zero-mode singular states and the topologically protected edge states in the thermodynamic limit. Our results formulate a bulk-boundary correspondence for Floquet non-Hermitian systems, where topology arises intrinsically from the driven non-Hermitian systems, even without symmetries. Our results provide a promising new avenue for exploring novel non-Hermitian topological phases.

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