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arXiv · 2408.08164

Critical assessment of information back-flow in measurement-free teleportation

Hannah McAleese·Mauro Paternostro
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Abstract

We assess a scheme for measurement-free quantum teleportation from the perspective of the resources underpinning its performance. In particular, we focus on recently made claims about the crucial role played by the degree of non-Markovianity of the dynamics of the information carrier whose state we aim to teleport. We prove that any link between efficiency of teleportation and back-flow of information depends fundamentally on the way the various operations entailed by the measurement-free teleportation protocol are implemented, while - in general - no claim of causal link can be made. Our result reinforces the need for the explicit assessment of the underlying physical platform when assessing the performance and resources for a given quantum protocol and the need for a rigorous quantum resource theory of non-Markovianity.

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Hannah McAleese, Mauro Paternostro. 2024-08-15. Critical assessment of information back-flow in measurement-free teleportation. https://doi.org/10.3390/e26090780

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