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arXiv · 2006.01059

A high fidelity heralded squeezing gate

Jie Zhao·Kui Liu·Jeng Hao·Mile Gu·Jayne Thompson·Ping Koy Lam·Syed Assad
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Abstract

A universal squeezing gate capable of squeezing arbitrary input states is essential for continuous-variable quantum computation~\cite{PRA79062318,PRL112120504}. However, in present state-of-the-art techniques~\cite{PRA90060302,PRL106240504}, the fidelity of such gates is ultimately limited by the need to create squeezed vacuum modes of unbounded energy. Here we circumvent this fundamental limitation by using a heralded squeezing gate. We propose and experimentally demonstrate a squeezing gate that can achieve near unit fidelity for coherent input states. In particular, for a target squeezing of \SI{2.3}{\dB}, we report a fidelity of \SI{98.5}{\%}. This result cannot be reproduced by conventional schemes even if the currently best available squeezing of \SI{15}{\dB}~\cite{PRL117110801} is utilised when benchmarked on identical detection inefficiencies. Our technique can be applied to non-Gaussian states and provides a promising pathway towards high-fidelity gate operations and fault-tolerant quantum computation.

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Jie Zhao, Kui Liu, Jeng Hao, Mile Gu, Jayne Thompson, Ping Koy Lam, Syed Assad. 2020-06-01. A high fidelity heralded squeezing gate. https://doi.org/10.1038/s41566-020-0592-2

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