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  • Letter
  • Open Access

Hybrid single-ion atomic-ensemble node for high-rate remote entanglement generation

Benedikt Tissot1,*, Soubhadra Maiti2,3, Emil R. Hellebek1, and Anders Søndberg Sørensen1,†

  • *Contact author: benedikt.tissot@nbi.ku.dk
  • †Contact author: anders.sorensen@nbi.ku.dk
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Phys. Rev. A 114, L010602 – Published 16 July, 2026

DOI: https://doi.org/10.1103/47zq-2h7t

Abstract

Different quantum systems possess different favorable qualities. On the one hand, ensemble-based quantum memories are suited for fast multiplexed long-range entanglement generation. On the other hand, single-atomic systems provide access to gates for processing of information. Both of those can provide advantages for high-rate entanglement generation within quantum networks. We develop a hybrid architecture that takes advantage of these properties by combining trapped-ion nodes and nodes comprised of spontaneous parametric down-conversion photon-pair sources and absorptive memories based on rare-earth ion ensembles. To this end, we solve the central challenge of matching the different bandwidths of photons emitted by those systems in an initial entanglement-generation step. This enables the parallel execution of multiple probabilistic tasks in the initial stage. As a particular example, we show that our approach can lead to a significant speed-up for the fundamental task of creating ion-ion entanglement over hundreds of kilometers in a quantum network.

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Single- and double-click high-rate entanglement generation between distant ions using multiplexed atomic ensembles

Benedikt Tissot, Soubhadra Maiti, Emil R. Hellebek, and Anders Søndberg Sørensen
Phys. Rev. Research 8, 033067 (2026)

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Phys. Rev. A 114, L010602– Published 16 July, 2026
  • Received 17 November 2025
  • Accepted 13 May 2026
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