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arXiv · 2109.14712

Violation of Bell's inequality with quantum-dot single-photon sources

Eva M. González-Ruiz·Sumanta K. Das·Peter Lodahl·Anders S. Sørensen
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Abstract

We investigate the possibility of realizing a loophole-free violation of Bell's inequality using deterministic single-photon sources. We provide a detailed analysis of a scheme to achieve such violations over long distances with immediate extensions to device-independent quantum key distribution. We investigate the effect of key experimental imperfections that are unavoidable in real-world single-photon sources including the finite degree of photon indistinguishability, single-photon purity, and the overall source efficiency. We benchmark the performance requirements to state-of-the-art deterministic single-photon sources based on quantum dots in photonic nanostructures and find that experimental realizations appear to be within reach. We also evaluate the requirements for a post-selected version of the protocol, which relaxes the demanding requirements with respect to the source efficiency.

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Eva M. González-Ruiz, Sumanta K. Das, Peter Lodahl, Anders S. Sørensen. 2021-09-29. Violation of Bell's inequality with quantum-dot single-photon sources. https://doi.org/10.1103/physreva.106.012222

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