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arXiv · 1409.1810

More Communication with Less Entanglement

P. Agrawal·Satyabrata Adhikari·Sumit Nandi
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Abstract

We exhibit the intriguing phenomena of "Less is More" using a set of multipartite entangled states. We consider the quantum communication protocols for the {\em exact} teleportation, superdense coding, and quantum key distribution. We find that sometimes {\em less} entanglement is {\em more} useful. To understand this phenomena we obtain a condition that a resource state must satisfy to communicate a $n$-qubit pure state with $m$ terms. We find that the an appropriate partition of the resource state should have a von-Neumann entropy of ${\rm log}_{2} m$. Furthermore, it is shown that some states may be suitable for exact superdense coding, but not for exact teleportation.

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P. Agrawal, Satyabrata Adhikari, Sumit Nandi. 2014-09-05. More Communication with Less Entanglement. https://doi.org/10.1140/epjd%2Fe2015-60525-5

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