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arXiv · 1706.06539

Multipartite entanglement in topological quantum phases

Luca Pezzè·Marco Gabbrielli·Luca Lepori·Augusto Smerzi
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Abstract

We witness multipartite entanglement in the Kitaev chain -- a benchmark model of one dimensional topological insulator -- also with variable-range pairing, using the quantum Fisher information. Phases having a finite winding number, both for short- and long-range pairing, are characterized by a power-law diverging finite-size scaling of multipartite entanglement. Moreover the occurring quantum phase transitions are sharply marked by the divergence of the derivative of the quantum Fisher information, even in the absence of a closing energy gap.

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Luca Pezzè, Marco Gabbrielli, Luca Lepori, Augusto Smerzi. 2017-06-20. Multipartite entanglement in topological quantum phases. https://doi.org/10.1103/physrevlett.119.250401

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