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General construction of noiseless networks detecting entanglement with help of linear maps

P. Horodecki·R. Augusiak·M. Demianowicz
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Abstract

We present the general scheme for construction of noiseless networks detecting entanglement with the help of linear, hermiticity-preserving maps. We show how to apply the method to detect entanglement of unknown state without its prior reconstruction. In particular, we prove there always exists noiseless network detecting entanglement with the help of positive, but not completely positive maps. Then the generalization of the method to the case of entanglement detection with arbitrary, not necessarily hermiticity-preserving, linear contractions on product states is presented.

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P. Horodecki, R. Augusiak, M. Demianowicz. 2007-11-06. General construction of noiseless networks detecting entanglement with help of linear maps. https://doi.org/10.1103/physreva.74.052323

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