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Entangling power of permutation invariant quantum states

Vladislav Popkov·Mario Salerno·Gunter Schuetz
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Abstract

We investigate the von Neumann entanglement entropy as function of the size of a subsystem for permutation invariant ground states in models with finite number of states per site, e.g., in quantum spin models. We demonstrate that the entanglement entropy of $n$ sites in a system of length $L$ generically grows as $\sigma\log_{2}[2\pi en(L-n)/L]+C$, where $\sigma$ is the on-site spin and $C$ is a function depending only on magnetization.

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Vladislav Popkov, Mario Salerno, Gunter Schuetz. 2005-06-24. Entangling power of permutation invariant quantum states. https://doi.org/10.1103/physreva.72.032327

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