Duke University and IonQ Demonstrate Tripartite Entanglement of Remote Atomic Qubits

Researchers from the Duke Quantum Center and IonQ have successfully demonstrated the distributed generation of a Greenberger–Horne–Zeilinger (GHZ) state across a three-node quantum network using trapped atomic ions. The experiment involved three hardware modules positioned two meters apart, connected via optical fibers to a central free-space GHZ-state generator. This configuration achieved remote tripartite entanglement without the need for local two-qubit gates or post-selection, maintaining state fidelities between 0.841 and 0.881.

Each node utilizes a single ¹³⁸Ba⁺ ion trapped in a Paul trap, with entanglement heralded by the detection of photons emitted from the ions. By aligning the polarizations of these photons and performing pairwise interference at beam splitters, the team erased which-path information, confirming the entanglement of the remote atomic memories. The researchers also conducted a deterministic test of quantum non-locality, measuring a Mermin parameter of 3.203, which exceeds the classical limit by 27 standard deviations.

This achievement serves as a significant milestone for modular quantum computing. By demonstrating that computational workloads can be distributed across interconnected quantum processing nodes rather than relying on a single monolithic system, this framework provides a practical engineering pathway for scaling quantum architectures, secure secret sharing, and distributed sensing.

Source: quantumcomputingreport.com
Publication date: 20.06.2026
Author: Mohamed Abdel-Kareem