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Multipartite entanglement in quantum spin chains

D. Bruss·N. Datta·A. Ekert·L. C. Kwek·C. Macchiavello
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Abstract

We study the occurrence of multipartite entanglement in spin chains. We show that certain genuine multipartite entangled states, namely W states, can be obtained as ground states of simple XX type ferromagnetic spin chains in a transverse magnetic field, for any number of sites. Moreover, multipartite entanglement is proven to exist even at finite temperatures. A transition from a product state to a multipartite entangled state occurs when decreasing the magnetic field to a critical value. Adiabatic passage through this point can thus lead to the generation of multipartite entanglement.

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D. Bruss, N. Datta, A. Ekert, L. C. Kwek, C. Macchiavello. 2005-05-30. Multipartite entanglement in quantum spin chains. https://doi.org/10.1103/physreva.72.014301

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