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Entanglement entropy of multipartite pure states

Sergei Bravyi
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Abstract

Consider a system consisting of $n$ $d$-dimensional quantum particles and arbitrary pure state $Ψ$ of the whole system. Suppose we simultaneously perform complete von Neumann measurements on each particle. One can ask: what is the minimal possible value $S[Ψ]$ of the entropy of outcomes joint probability distribution? We show that $S[Ψ]$ coincides with entanglement entropy for bipartite states. We compute $S[Ψ]$ for two sample multipartite states: the hexacode state ($n=6, d=2$) and determinant states ($n=d$). The generalization of determinant states to the case $d<n$ is considered.

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Sergei Bravyi. 2002-05-13. Entanglement entropy of multipartite pure states. https://doi.org/10.1103/physreva.67.012313

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