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Two-way and three-way negativities of three qubit entangled states

S. Shelly Sharma·N. K. Sharma
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Abstract

We propose to quantify three qubit entanglement using global negativity along with K-way negativities, where K=2 and 3. K-way partial transpose with respect to a subsystem is defined so as to shift the focus to K-way coherences of the composite system instead of K subsystems of the composite system. While genuine tripartite entanglement of three qubit composite system is generated by 3-way coherences, tripartite entanglement can be present due to 2-way coherences as well.

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S. Shelly Sharma, N. K. Sharma. 2007-01-04. Two-way and three-way negativities of three qubit entangled states. https://doi.org/10.1103/physreva.76.012326

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