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arXiv · 1703.04709

Entanglement between more than two hundred macroscopic atomic ensembles in a solid

P. Zarkeshian·C. Deshmukh·N. Sinclair·S. K. Goyal·G. H. Aguilar·P. Lefebvre·M. Grimau Puigibert·V. B. Verma·F. Marsili·M. D. Shaw·S. W. Nam·K. Heshami·D. Oblak·W. Tittel·C. Simon
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Abstract

We create a multi-partite entangled state by storing a single photon in a crystal that contains many large atomic ensembles with distinct resonance frequencies. The photon is re-emitted at a well-defined time due to an interference effect analogous to multi-slit diffraction. We derive a lower bound for the number of entangled ensembles based on the contrast of the interference and the single-photon character of the input, and we experimentally demonstrate entanglement between over two hundred ensembles, each containing a billion atoms. In addition, we illustrate the fact that each individual ensemble contains further entanglement. Our results are the first demonstration of entanglement between many macroscopic systems in a solid and open the door to creating even more complex entangled states.

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P. Zarkeshian, C. Deshmukh, N. Sinclair, S. K. Goyal, G. H. Aguilar, P. Lefebvre, M. Grimau Puigibert, V. B. Verma, F. Marsili, M. D. Shaw, S. W. Nam, K. Heshami, D. Oblak, W. Tittel, C. Simon. 2017-03-14. Entanglement between more than two hundred macroscopic atomic ensembles in a solid. https://doi.org/10.1038/s41467-017-00897-7

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