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arXiv · 1101.3654

Quantum phase transitions in fully connected spin models: an entanglement perspective

M. Filippone·S. Dusuel·J. Vidal
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Abstract

We consider a set of fully connected spins models that display first- or second-order transitions and for which we compute the ground-state entanglement in the thermodynamical limit. We analyze several entanglement measures (concurrence, Rényi entropy, and negativity), and show that, in general, discontinuous transitions lead to a jump of these quantities at the transition point. Interestingly, we also find examples where this is not the case.

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M. Filippone, S. Dusuel, J. Vidal. 2011-02-28. Quantum phase transitions in fully connected spin models: an entanglement perspective. https://doi.org/10.1103/physreva.83.022327

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