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arXiv · 1010.6049

Taming multiparticle entanglement

Bastian Jungnitsch·Tobias Moroder·Otfried Gühne
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Abstract

We present an approach to characterize genuine multiparticle entanglement using appropriate approximations in the space of quantum states. This leads to a criterion for entanglement which can easily be calculated using semidefinite programming and improves all existing approaches significantly. Experimentally, it can also be evaluated when only some observables are measured. Furthermore, it results in a computable entanglement monotone for genuine multiparticle entanglement. Based on this, we develop an analytical approach for the entanglement detection in cluster states, leading to an exponential improvement compared with existing schemes.

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Bastian Jungnitsch, Tobias Moroder, Otfried Gühne. 2011-05-12. Taming multiparticle entanglement. https://doi.org/10.1103/physrevlett.106.190502

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