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arXiv · 0707.1164

Quantum coherences, K-way negativities and multipartite entanglement

S. Shelly Sharma·N. K. Sharma
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Abstract

A characterization of N-partite states, based on K-way (K = 2 to N) negativities, is proposed. The K-way partial transpose with respect to a subsystem is defined so as to shift the focus to K-way coherences instead of K subsystems of the composite system. For an N-partite system the fraction of K-way negativity, contributing to global negativity, is obtained. The entanglement measures for a given state $ρ$ are identified as the partial K-way negativities of the corresponding canonical state.

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S. Shelly Sharma, N. K. Sharma. 2008-04-01. Quantum coherences, K-way negativities and multipartite entanglement. https://doi.org/10.1103/physreva.77.042117

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