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arXiv · 2405.19067

Implementing arbitrary multi-mode continuous-variable quantum gates with fixed non-Gaussian states and adaptive linear optics

Fumiya Hanamura·Warit Asavanant·Hironari Nagayoshi·Atsushi Sakaguchi·Ryuhoh Ide·Kosuke Fukui·Peter van Loock·Akira Furusawa
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Abstract

Non-Gaussian quantum gates are essential components for optical quantum information processing. However, the efficient implementation of practically important multi-mode higher-order non-Gaussian gates has not been comprehensively studied. We propose a measurement-based method to directly implement general, multi-mode, and higher-order non-Gaussian gates using only fixed non-Gaussian ancillary states and adaptive linear optics. Compared to existing methods, our method allows for a more resource-efficient and experimentally feasible implementation of multi-mode gates that are important for various applications in optical quantum technology, such as the two-mode cubic quantum non-demolition gate or the three-mode continuous-variable Toffoli gate, and their higher-order extensions. Our results will expedite the progress toward fault-tolerant universal quantum computing with light.

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Fumiya Hanamura, Warit Asavanant, Hironari Nagayoshi, Atsushi Sakaguchi, Ryuhoh Ide, Kosuke Fukui, Peter van Loock, Akira Furusawa. 2024-05-29. Implementing arbitrary multi-mode continuous-variable quantum gates with fixed non-Gaussian states and adaptive linear optics. https://doi.org/10.1103/physreva.110.022614

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