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arXiv · 2404.06438

Non-Gaussian state teleportation with a nonlinear feedforward

Vojtěch Kala·Mattia Walschaers·Radim Filip·Petr Marek
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Abstract

Measurement-induced quantum computation with continuous-variable cluster states utilizes teleportation to transmit and alter quantum states via measurement-and-feedforward control. One of the key challenges of this approach is the deterioration of quantum states caused by the noise added due to imperfect entanglement of the cluster. We analyze the propagation of a quantum non-Gaussian state with nonlinear squeezing through a small cluster state. We show that a nonlinear feedforward in the deterministic teleportation protocol reduces the added noise and improves the nonlinear squeezing transferred. In a probabilistic regime, the improvement can be manifested even with current experimental resources. Better processing of non-Gaussian states can bring us closer to the necessary interplay between cluster states and non-Gaussianity required by quantum computing.

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Vojtěch Kala, Mattia Walschaers, Radim Filip, Petr Marek. 2024-04-09. Non-Gaussian state teleportation with a nonlinear feedforward. https://doi.org/10.1103/4k4w-dc3l

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