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arXiv · 0909.0580

Channel Capacities versus Entanglement Measures in Multiparty Quantum States

Aditi Sen De·Ujjwal Sen
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Abstract

For quantum states of two subsystems, entanglement measures are related to capacities of communication tasks -- highly entangled states give higher capacity of transmitting classical as well as quantum information. However, we show that this is no more the case in general: quantum capacities of multi-access channels, motivated by communication in quantum networks, do not have any relation with genuine multiparty entanglement measures. Along with revealing the structural richness of multi-access channel capacities, this gives us a tool to classify multiparty quantum states from the perspective of its usefulness in quantum networks, which cannot be visualized by known multiparty entanglement measures.

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Aditi Sen De, Ujjwal Sen. 2009-09-03. Channel Capacities versus Entanglement Measures in Multiparty Quantum States. https://doi.org/10.1103/physreva.81.012308

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