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arXiv · 2506.14334

Multipartite Mixed-Species Entanglement over a Quantum Network

D. Main·P. Drmota·E. M. Ainley·A. Agrawal·D. Webb·S. Saner·O. Bazavan·B. C. Nichol·R. Srinivas·D. P. Nadlinger·G. Araneda·D. M. Lucas
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Abstract

We generate multipartite entangled states of two, three and four matter qubits, where the entanglement is distributed over macroscopic distances via a photonic network link. Trapped-ion ${}^{88}\text{Sr}^+$ qubits are entangled directly via the optical fibre link, and the entanglement is subsequently extended to ${}^{43}\text{Ca}^+$ memory qubits co-trapped in each network node, using local mixed-species logic gates. We create remotely entangled $\text{Sr}^+$-$\text{Ca}^+$ and $\text{Ca}^+$-$\text{Ca}^+$ states, as well as mixed-species Greenberger-Horne-Zeilinger (GHZ) states of up to four qubits. We demonstrate storage of the remotely-entangled memory qubits for $\sim10~\text{s}$, more than $100\times$ the creation time.

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D. Main, P. Drmota, E. M. Ainley, A. Agrawal, D. Webb, S. Saner, O. Bazavan, B. C. Nichol, R. Srinivas, D. P. Nadlinger, G. Araneda, D. M. Lucas. 2025-06-17. Multipartite Mixed-Species Entanglement over a Quantum Network. https://arxiv.org/abs/2506.14334

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