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Multipartite Mixed-Species Entanglement over a Quantum Network

D. Main*,†, P. Drmota, E. M. Ainley, A. Agrawal, D. Webb, S. Saner, O. Bǎzǎvan, B. C. Nichol, R. Srinivas et al.

D. P. Nadlinger, G. Araneda‡, and D. M. Lucas

  • *Present address: Oxford Ionics, Oxford, OX5 1GN United Kingdom.
  • †Contact author: dougal.main@oxionics.com
  • ‡Contact author: gabriel.aranedamachuca@physics.ox.ac.uk
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Phys. Rev. Lett. 137, 160801 – Published 13 October, 2026

DOI: https://doi.org/10.1103/qpsf-nlp9

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 Sr+88 qubits are entangled directly via an optical fibre link, and the entanglement is subsequently extended to Ca+43 memory qubits cotrapped in each network node, using local mixed-species logic gates. We create remotely entangled Sr+−Ca+ and Ca+−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 ∼10  s, more than 100× the state creation time.

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Phys. Rev. Lett. 137, 160801– Published 13 October, 2026
  • Received 4 January 2026
  • Revised 11 April 2026
  • Accepted 15 May 2026
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