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arXiv · 2404.06514

Disentangling transitions in topological order induced by boundary decoherence

Tsung-Cheng Lu
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Abstract

We study the entanglement structure of topological orders subject to decoherence on the bipartition boundary. Focusing on the toric codes in $d$ space dimensions for $d=2,3,4$, we explore whether the boundary decoherence may be able to induce a disentangling transition, characterized by the destruction of mixed-state long-range entanglement across the bipartition, measured by topological entanglement negativity. A key insight of our approach is the connection between the negativity spectrum of the decohered mixed states and emergent symmetry-protected topological orders under certain symmetry-preserving perturbation localized on the bipartition boundary. This insight allows us to analytically derive the exact results of entanglement negativity without using a replica trick.

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Tsung-Cheng Lu. 2024-04-09. Disentangling transitions in topological order induced by boundary decoherence. https://doi.org/10.1103/physrevb.110.125145

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