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arXiv · 2411.09350

Nonlinear protocol for high-dimensional quantum teleportation

Luca Bianchi·Carlo Marconi·Giulia Guarda·Davide Bacco
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Abstract

Bell measurements, which allow entanglement between uncorrelated distant particles, play a central role in quantum communication. Indeed sharing, measuring and creating entanglement lie at the core of various protocols, such as entanglement swapping and quantum teleportation. While for optical qubit systems a Bell measurement can be implemented using only linear components, the same result is no longer true for high-dimensional states, where one has to consider either ancillary photons or nonlinear processes. Here, inspired by the latter approach, we propose a protocol for high-dimensional quantum teleportation based on nonlinear techniques. Moreover, we discuss the practical implementation of our proposed setup in the case of path-encoded qutrits, where nonlinear effects arise from sum-frequency generation. Finally, we compute the fidelity between quantum states to benchmark the validity of our model under the presence of crosstalk noise. Our approach is deterministic, scalable and does not rely on the use of auxiliary photons, thus paving the way towards the practical implementation of quantum networks based on nonlinear effects.

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Luca Bianchi, Carlo Marconi, Giulia Guarda, Davide Bacco. 2024-11-14. Nonlinear protocol for high-dimensional quantum teleportation. https://doi.org/10.1103/3x44-664w

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