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arXiv · 2501.16878

Port-based telecloning of an unknown quantum state

Reiji Okada·Kohtaro Kato·Francesco Buscemi
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Abstract

Telecloning is a protocol introduced by Murao et al. [Phys. Rev. A 59, 156 (1999)] to distribute copies of an unknown quantum state to many receivers in a way that beats the trivial ``clone-and-teleport'' protocol. In the last decade, a new type of teleportation called port-based teleportation, in which the receiver can recover the state without having to actively perform correction operations, but simply by looking at the correct port, has been widely studied. In this paper, we consider the analog of telecloning, where conventional teleportation is replaced by the port-based variant. To achieve this, we generalize the optimal measurement used in port-based teleportation and develop a new one that achieves port-based telecloning. Numerical results show that, in certain cases, the proposed protocol is strictly better than the trivial clone-and-teleport approach.

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Reiji Okada, Kohtaro Kato, Francesco Buscemi. 2025-01-28. Port-based telecloning of an unknown quantum state. https://doi.org/10.1103/physreva.111.052408

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