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Genuine tripartite entanglement as a probe of quantum phase transitions in a spin-1 Heisenberg chain with single-ion anisotropy

We study the quantum phase transitions of spin-1 Heisenberg chains with an easy-axis anisotropy $Δ$ and a uniaxial single-ion anisotropy $D$ using a multipartite entanglement approach. The genuine tripartite entanglement between the spin blocks, measured by the tripartite qutrit hyperdeterminant, is calculated within the quantum renormalization group method. Using this approach, the phase boundaries between the topological Haldane, large-D and anti-ferromagnetic Néel phases are determined in the half $Δ-D$ plane with $Δ>0$. When the size of the spin blocks increases, the genuine tripartite entanglement between the blocks exhibits a nonzero plateau in the topological Haldane phase, and experiences abrupt drops at both the phase boundaries between the Haldane--large-D and Haldane--Néel phases, which justifies the usage of genuine multipartite entanglement as a probe of topological phases in spin systems.