The world's first three-node quantum network based on individual atoms: a breakthrough toward the quantum internet
A research group from Duke University and IonQ has taken a significant step in the field of distributed quantum computing. Specialists have, for the first time, successfully created a fully distributed three-node quantum network based on individual atomic qubits connected by photonic communication channels.
Technical Essence of the Achievement
The key result of the experiment was the formation of a so-called three-party entangled state (Greenberger-Horne-Zeilinger state) between three remote quantum nodes. This state, where a change in the properties of one particle is instantly reflected in all others regardless of distance, is the foundation for future quantum communications. The fidelity of the obtained entangled state was 84–88%, which is an impressive figure for such systems.
Of particular note is the fact that the researchers managed, for the first time, to close the so-called "detection loophole" for a fully distributed multi-component quantum state. Additionally, the results confirmed the violation of the Mermin inequality — one of the key tests proving the presence of genuine quantum correlations rather than classical statistical coincidences.
Why This Matters for the Industry
The main problem with modern quantum computers is scaling. Creating a single large quantum processor faces colossal engineering difficulties due to decoherence errors and equipment limitations. This is why many developers are betting on a modular architecture: instead of a monolithic chip, a network of many quantum nodes connected by photons is created. This approach resembles the evolution of the classical internet, where computing resources are distributed across thousands of servers.
The new experiment clearly demonstrates that individual atomic memories can form a common quantum state through photonic connections while maintaining high precision of quantum operations. This is a critically important building block for future distributed quantum computers, secure communication networks, and ultimately, the quantum internet.
Looking to the Future
The work continues a series of IonQ studies in the field of photonic quantum connections. Previously, the company demonstrated entanglement between two remote ion systems, and has now expanded the architecture to three full nodes. Although the technology is still far from commercial application, such experiments are the foundation upon which the next generation of computing systems will be built.
My Expert Assessment: This achievement marks a transition from laboratory demonstrations of two-node entanglement to scalable network architectures. If IonQ and other players can maintain fidelity above 80% while increasing the number of nodes to dozens, we will witness the emergence of the first prototypes of the quantum internet within the next 5-7 years. Investors should closely monitor this direction — it could change the landscape of cybersecurity and high-performance computing.