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arXiv · 1206.4928

Energy as witness of multipartite entanglement in spin clusters

F. Troiani·I. Siloi
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Abstract

We derive energy minima for biseparable states in three- and four-spin systems, with Heisenberg Hamiltonian and s <= 5/2. These provide lower bounds for tripartite and quadripartite entanglement in chains and rings with larger spin number N. We demonstrate that the ground state of an $N$-spin Heisenberg chain is $N$-partite entangled, and compute the energy gap with respect to biseparable states for N <= 8.

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F. Troiani, I. Siloi. 2012-06-21. Energy as witness of multipartite entanglement in spin clusters. https://doi.org/10.1103/physreva.86.032330

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