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Entanglement entropy in the Lipkin-Meshkov-Glick model

J. I. Latorre·R. Orus·E. Rico·J. Vidal
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Abstract

We analyze the entanglement entropy in the Lipkin-Meshkov-Glick model, which describes mutually interacting spins half embedded in a magnetic field. This entropy displays a singularity at the critical point that we study as a function of the interaction anisotropy, the magnetic field, and the system size. Results emerging from our analysis are surprisingly similar to those found for the one-dimensional XY chain.

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J. I. Latorre, R. Orus, E. Rico, J. Vidal. 2005-06-03. Entanglement entropy in the Lipkin-Meshkov-Glick model. https://doi.org/10.1103/physreva.71.064101

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