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Persistent entanglement in arrays of interacting particles

Hans J. Briegel·Robert Raussendorf
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Abstract

We study the entanglement properties of a class of $N$ qubit quantum states that are generated in arrays of qubits with an Ising-type interaction. These states contain a large amount of entanglement as given by their Schmidt measure. They have also a high {\em persistency of entanglement} which means that $\sim N/2$ qubits have to be measured to disentangle the state. These states can be regarded as an entanglement resource since one can generate a family of other multi-particle entangled states such as the generalized GHZ states of $<N/2$ qubits by simple measurements and classical communication (LOCC).

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Hans J. Briegel, Robert Raussendorf. 2000-08-28. Persistent entanglement in arrays of interacting particles. https://doi.org/10.1103/physrevlett.86.910

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