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arXiv · 2408.08667

Improving Gaussian channel simulation using non-unity gain heralded quantum teleportation

Biveen Shajilal·Lorcán O. Conlon·Angus Walsh·Spyros Tserkis·Jie Zhao·Jiri Janousek·Syed Assad·Ping Koy Lam
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Abstract

Gaussian channel simulation is an essential paradigm in understanding the evolution of bosonic quantum states. It allows us to investigate how such states are influenced by the environment and how they transmit quantum information. This makes it an essential tool for understanding the properties of Gaussian quantum communication. Quantum teleportation provides an avenue to effectively simulate Gaussian channels such as amplifier channels, loss channels and classically additive noise channels. However, implementations of these channels, particularly quantum amplifier channels and channels capable of performing Gaussian noise suppression are limited by experimental imperfections and non-ideal entanglement resources. In this work, we overcome these difficulties using a heralded quantum teleportation scheme that is empowered by a measurement-based noiseless linear amplifier. The noiseless linear amplification enables us to simulate a range of Gaussian channels that were previously inaccessible. In particular, we demonstrate the simulation of non-physical Gaussian channels otherwise inaccessible using conventional means. We report Gaussian noise suppression, effectively converting an imperfect quantum channel into a near-identity channel. The performance of Gaussian noise suppression is quantified by calculating the transmitted entanglement.

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Biveen Shajilal, Lorcán O. Conlon, Angus Walsh, Spyros Tserkis, Jie Zhao, Jiri Janousek, Syed Assad, Ping Koy Lam. 2024-08-16. Improving Gaussian channel simulation using non-unity gain heralded quantum teleportation. https://arxiv.org/abs/2408.08667

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