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arXiv · 0711.3882

Entanglement in an SU(n) Valence-Bond-Solid State

Hosho Katsura·Takaaki Hirano·Vladimir E. Korepin
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Abstract

We investigate entanglement properties in the ground state of the open/periodic SU($n$) generalized valence-bond-solid state consisting of representations of SU($n$). We obtain exact expression for the reduced density matrix of a block of contiguous spins and explicitly evaluate the von Neumann and the Rényi entropies. We discover that the Rényi entropy is independent of the parameter $α$ in the limit of large block sizes and its value $2 \log n$ coincides with that of von Neumann entropy. We also find the direct relation between the reduced density matrix of the subsystem and edge states for the corresponding open boundary system.

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Hosho Katsura, Takaaki Hirano, Vladimir E. Korepin. 2007-12-28. Entanglement in an SU(n) Valence-Bond-Solid State. https://doi.org/10.1088/1751-8113%2F41%2F13%2F135304

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