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arXiv · 2212.13335

Non-Gaussian state generation with time-gated photon detection

Tatsuki Sonoyama·Kazuma Takahashi·Baramee Charoensombutamon·Sachiko Takasu·Kaori Hattori·Daiji Fukuda·Kosuke Fukui·Kan Takase·Warit Asavanant·Jun-ichi Yoshikawa·Mamoru Endo·Akira Furusawa
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Abstract

Non-Gaussian states of light, which are essential in fault-tolerant and universal optical quantum computation, are typically generated by a heralding scheme using photon detectors. Recently, it is theoretically shown that the large timing jitter of the photon detectors deteriorates the purity of the generated non-Gaussian states [T. Sonoyama, $\textit{et al}$., Phys. Rev. A $\textbf{105}$, 043714 (2022)]. In this study, we generate non-Gaussian states with Wigner negativity by time-gated photon detection. We use a fast optical switch for time gating to effectively improve the timing jitter of a photon-number-resolving detector based on transition edge sensor from 50 ns to 10 ns. As a result, we generate non-Gaussian states with Wigner negativity of $-0.011\pm 0.004$, which cannot be observed without the time-gated photon detection method. These results confirm the effect of the timing jitter on non-Gaussian state generation experimentally for the first time and provide the promising method of high-purity non-Gaussian state generation.

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Tatsuki Sonoyama, Kazuma Takahashi, Baramee Charoensombutamon, Sachiko Takasu, Kaori Hattori, Daiji Fukuda, Kosuke Fukui, Kan Takase, Warit Asavanant, Jun-ichi Yoshikawa, Mamoru Endo, Akira Furusawa. 2022-12-27. Non-Gaussian state generation with time-gated photon detection. https://doi.org/10.1103/physrevresearch.5.033156

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