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arXiv · 2406.09278

Boosting information transfer in a quantum correlated medium

Finn Schmolke·Etienne Springer·Eric Lutz
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Abstract

Sharing and receiving information plays a pivotal role in science and technology. Quantum communication relies on the principles of quantum mechanics to transmit information in a nonclassical manner. Existing quantum communication protocols are commonly based on shared entangled states between sender and receiver, while the transmitting medium is classical. We here demonstrate that information transfer may be enhanced in a quantum correlated medium without entanglement distribution. We concretely show that nonclassical correlations, with nonzero discord, between the first two spins of a spin chain that acts as a quantum wire can increase the information flow and reduce the propagation time. We relate this effect to the breaking of the spatial symmetry of the out-of-time-order correlator that characterizes the spread of information through the medium.

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Finn Schmolke, Etienne Springer, Eric Lutz. 2024-06-13. Boosting information transfer in a quantum correlated medium. https://arxiv.org/abs/2406.09278

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