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arXiv · 1011.3277

Topological disentangler for the valence-bond-solid chain

Kouichi Okunishi
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Abstract

We discuss topological disentangler for S=1 quantum spin chains in the Haldane phase. We first point out that Kennedy-Tasaki's(KT) nonlocal unitary transformation is the perfect disentangler for Affleck-Kennedy-Lieb-Tasaki model. We then demonstrate that the KT transformation can be reconstructed as an assembly of pair disentanglers. Finally, we show that the KT transformation can be regarded as a topological disentangler, which selectively disentangles the double-fold degeneracy in the entanglement spectrum of the S=1 Heisenberg chain.

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Kouichi Okunishi. 2010-11-15. Topological disentangler for the valence-bond-solid chain. https://doi.org/10.1103/physrevb.83.104411

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