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arXiv · 2504.00710

Entanglement recycling in two-step port-based teleportation

Piotr Kopszak·Dmitry Grinko·Adam Burchardt·Maris Ozols·Michał Studziński·Marek Mozrzymas
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Abstract

A protocol involving the repetitive (twofold, to be precise) application of PBT protocol to the same resource is studied. The quantities characterizing the resulting protocol, so-called \textit{two-step PBT}, namely \textit{enatnglement fidelity} and \textit{success probability} are provided for two scenarios, relying on application of pretty-good measurement, i.e. deterministic and probabilistic PBT with non-EPR resource. This results show that two-step PBT is an accurate protocol, provided the resource is sufficiently large. In particular, the deterministic two-step PBT obtains fidelity that is remarkably close to the optimal MPBT fidelity for teleportation of two quantum states. Additionally, the \textit{recycling fidelity}, i.e. the quantity characterizing the degradation of the resource state is calculated for repetitive application of probabilistic protocol, for both EPR and optimized resource, showing that entanglement recycling with two-step PBT is possible in the former case as well.

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Piotr Kopszak, Dmitry Grinko, Adam Burchardt, Maris Ozols, Michał Studziński, Marek Mozrzymas. 2025-04-01. Entanglement recycling in two-step port-based teleportation. https://doi.org/10.1109/tit.2026.3656762

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