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arXiv · 1707.02449

Deterministic Quantum Dense Coding Networks

Saptarshi Roy·Titas Chanda·Tamoghna Das·Aditi Sen De·Ujjwal Sen
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Abstract

We consider the scenario of deterministic classical information transmission between multiple senders and a single receiver, when they a priori share a multipartite quantum state -- an attempt towards building a deterministic dense coding network. Specifically, we prove that in the case of two or three senders and a single receiver, generalized Greenberger-Horne-Zeilinger (gGHZ) states are not beneficial for sending classical information deterministically beyond the classical limit, except when the shared state is the GHZ state itself. On the other hand, three- and four-qubit generalized W (gW) states with specific parameters as well as the four-qubit Dicke states can provide a quantum advantage of sending the information in deterministic dense coding. Interestingly however, numerical simulations in the three-qubit scenario reveal that the percentage of states from the GHZ-class that are deterministic dense codeable is higher than that of states from the W-class.

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Saptarshi Roy, Titas Chanda, Tamoghna Das, Aditi Sen De, Ujjwal Sen. 2018-06-14. Deterministic Quantum Dense Coding Networks. https://doi.org/10.1016/j.physleta.2018.04.033

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