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arXiv · 2010.14788

Heralded non-destructive quantum entangling gate with single-photon sources

Jin-Peng Li·Xuemei Gu·Jian Qin·Dian Wu·Xiang You·Hui Wang·Christian Schneider·Sven Höfling·Yong-Heng Huo·Chao-Yang Lu·Nai-Le Liu·Li Li·Jian-Wei Pan
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Abstract

Heralded entangling quantum gates are an essential element for the implementation of large-scale optical quantum computation. Yet, the experimental demonstration of genuine heralded entangling gates with free-flying output photons in linear optical system, was hindered by the intrinsically probabilistic source and double-pair emission in parametric down-conversion. Here, by using an on-demand single-photon source based on a semiconductor quantum dot embedded in a micro-pillar cavity, we demonstrate a heralded controlled-NOT (CNOT) operation between two single photons for the first time. To characterize the performance of the CNOT gate, we estimate its average quantum gate fidelity of ($87.8\pm1.2$)%. As an application, we generated event-ready Bell states with a fidelity of ($83.4\pm2.4$)%. Our results are an important step towards the development of photon-photon quantum logic gates.

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Jin-Peng Li, Xuemei Gu, Jian Qin, Dian Wu, Xiang You, Hui Wang, Christian Schneider, Sven Höfling, Yong-Heng Huo, Chao-Yang Lu, Nai-Le Liu, Li Li, Jian-Wei Pan. 2021-01-16. Heralded non-destructive quantum entangling gate with single-photon sources. https://doi.org/10.1103/physrevlett.126.140501

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