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arXiv · 0903.3910

Practical methods for witnessing genuine multi-qubit entanglement in the vicinity of symmetric states

Geza Toth·Witlef Wieczorek·Roland Krischek·Nikolai Kiesel·Patrick Michelberger·Harald Weinfurter
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Abstract

We present general numerical methods to construct witness operators for entanglement detection and estimation of the fidelity. Our methods are applied to detecting entanglement in the vicinity of a six-qubit Dicke state with three excitations and also to further entangled symmetric states. All our witnesses are designed to keep the measurement effort small. We present also general results on the efficient local decomposition of permutationally invariant operators, which makes it possible to measure projectors to symmetric states efficiently

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Geza Toth, Witlef Wieczorek, Roland Krischek, Nikolai Kiesel, Patrick Michelberger, Harald Weinfurter. 2009-08-18. Practical methods for witnessing genuine multi-qubit entanglement in the vicinity of symmetric states. https://doi.org/10.1088/1367-2630%2F11%2F8%2F083002

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