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arXiv · 2004.09964

Efficient generation of high-dimensional entanglement through multi-path downconversion

Xiao-Min Hu·Wen-Bo Xing·Bi-Heng Liu·Yun-Feng Huang·Chuan-Feng Li·Guang-Can Guo·Paul Erker·Marcus Huber
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Abstract

High-dimensional entanglement promises to greatly enhance the performance of quantum communication and enable quantum advantages unreachable by qubit entanglement. One of the great challenges, however, is the reliable production, distribution and local certification of high-dimensional sources of entanglement. In this article, we present an optical setup capable of producing quantum states with an exceptionally high-level of scalability, control and quality, that, together with novel certification techniques, achieve the highest amount of entanglement recorded so far. We showcase entanglement in $32$-spatial dimensions with record fidelity to the maximally entangled state ($F=0.933\pm0.001$) and introduce measurement efficient schemes to certify entanglement of formation ($E_{oF}=3.728\pm0.006$). Combined with the existing multi-core fibre technology, our results will lay a solid foundation for the construction of high-dimensional quantum networks.

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Xiao-Min Hu, Wen-Bo Xing, Bi-Heng Liu, Yun-Feng Huang, Chuan-Feng Li, Guang-Can Guo, Paul Erker, Marcus Huber. 2020-04-21. Efficient generation of high-dimensional entanglement through multi-path downconversion. https://doi.org/10.1103/physrevlett.125.090503

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