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Qubit entanglement in multimagnon states

J. S. Pratt
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Abstract

The qubit entanglement induced by quasiparticle excitations in the Heisenberg spin chain and its relationship to the Bethe Ansatz structure of the eigenmodes is studied. A phenomenon called entanglement quenching, which suppresses eigenstate entanglement, is described and shown to be mediated by Goldstone magnons. Scattering states are characterized by short-range entanglement, and never exhibit entanglement at the longest range. In contrast, bound states have complex long-range entanglement structures.

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J. S. Pratt. 2005-05-17. Qubit entanglement in multimagnon states. https://doi.org/10.1103/physrevb.73.184413

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