Channel Capacities versus Entanglement Measures in Multiparty Quantum States

TL;DR

This paper demonstrates that in multi-party quantum states, unlike bipartite cases, quantum capacities are not directly related to multiparty entanglement measures, revealing new structural insights for quantum network applications.

Contribution

It shows the lack of correlation between quantum capacities and multiparty entanglement measures in multi-access channels, offering a new classification tool for quantum states.

Findings

Quantum capacities do not correlate with multiparty entanglement measures.

Multi-access channel capacities reveal structural richness of quantum states.

New classification method for quantum states based on network usefulness.

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.