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arXiv · 2507.20430

Entanglement Halos

Nadir Samos Sáenz de Buruaga·Silvia N. Santalla·Germán Sierra·Javier Rodríguez-Laguna
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Abstract

We introduce the concept of entanglement halos, a set of strongly entangled distant sites within the ground state of a quantum many-body system. Such halos emerge in star-like systems with exponentially decaying couplings, as we show using both free-fermions and the spin-1/2 antiferromagnetic Heisenberg model. Depending on the central connectivity, entanglement halos may exhibit trivial and non trivial symmetry-protected topological features. Our findings highlight how geometry and connectivity can generate complex entanglement structures with rich physical content, which can be experimentally accessible via state-of-the-art technologies.

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Nadir Samos Sáenz de Buruaga, Silvia N. Santalla, Germán Sierra, Javier Rodríguez-Laguna. 2025-07-27. Entanglement Halos. https://doi.org/10.1103/fddq-8lzl

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