Remote entanglement between stable quantum memories – mediated by optical photons – will likely be a critical component in fully scalable quantum computers, and there has been great progress over the last decade on improving the rate and fidelity of such quantum interconnects. We have recently extended this idea to three trapped atomic ions in separate vacuum chambers, heralded in a GHZ-entangled state with fidelity of 86% and rate of 0.1/sec. We measure a clear violation of Mermin’s inequality, while closing the detection loophole for the first time in a fully-distributed multipartite entangled state.
- “Tripartite entanglement of remote atomic qubits,” I. Goetting, et al., arXiv:2606.17173 (2026).
- See also concurrent results with 3 neutral atom + cavity nodes from the Max Planck Institute for Quantum Optics, “Efficient entanglement of three remote single-atom quantum-network nodes,” M. Seubert, et al., arXiv:2606.32006 (2006).
