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Entanglement and Spontaneous Symmetry Breaking in Quantum Spin Models

Olav F. Syljuasen
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Abstract

It is shown that spontaneous symmetry breaking does not modify the ground-state entanglement of two spins, as defined by the concurrence, in the XXZ- and the transverse field Ising-chain. Correlation function inequalities, valid in any dimensions for these models, are presented outlining the regimes where entanglement is unaffected by spontaneous symmetry breaking.

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Olav F. Syljuasen. 2003-07-11. Entanglement and Spontaneous Symmetry Breaking in Quantum Spin Models. https://doi.org/10.1103/physreva.68.060301

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