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arXiv · 0704.2414

Multi-qubit stabilizer and cluster entanglement witnesses

M. A. Jafarizadeh·G. Najarbashi·Y. Akbari·H. Habibian
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Abstract

One of the problems concerning entanglement witnesses (EWs) is the construction of them by a given set of operators. Here several multi-qubit EWs called stabilizer EWs are constructed by using the stabilizer operators of some given multi-qubit states such as GHZ, cluster and exceptional states. The general approach to manipulate the multi-qubit stabilizer EWs by exact(approximate) linear programming (LP) method is described and it is shown that the Clifford group play a crucial role in finding the hyper-planes encircling the feasible region. The optimality, decomposability and non-decomposability of constructed stabilizer EWs are discussed.

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M. A. Jafarizadeh, G. Najarbashi, Y. Akbari, H. Habibian. 2007-10-01. Multi-qubit stabilizer and cluster entanglement witnesses. https://doi.org/10.1140/epjd%2Fe2008-00028-0

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