The first-ever three-node quantum network based on individual atoms: a breakthrough towards the quantum internet
The world of quantum computing has taken another decisive step forward. A team of researchers from Duke University and IonQ announced the creation of the first fully distributed three-node quantum network, using individual atomic qubits as computing units. This is not just a laboratory curiosity, but a fundamental breakthrough that brings us closer to the era of a practical quantum internet.
What exactly happened
The key achievement is the formation of a so-called three-party entangled state (GHZ state, named after Greenberger—Horne—Zeilinger) between three remote quantum nodes. These nodes are connected via photonic channels, and the state of each is instantly correlated with the state of the others, regardless of distance.
Previously, scientists demonstrated entanglement between two nodes and also created three-node networks on other physical platforms (e.g., superconducting circuits). However, this is the first time such a result has been achieved specifically with individual atomic qubits. This is critically important because such qubits possess unique properties: they can be independently controlled, read out, and, most importantly, scaled to build real computing systems.
Why this changes the game
The main problem with modern quantum computers is scaling. Building one giant processor from thousands of qubits is incredibly difficult due to error accumulation and physical limitations. This is precisely why the industry is gradually moving toward a modular architecture. Instead of one "monolithic" quantum computer, a network of many quantum nodes connected by photons is created. This resembles the evolution of the classical internet, where computing power is distributed across thousands of servers.
The new experiment is a clear demonstration that this approach works. The researchers showed that individual atomic memories can form a shared quantum state through photonic connections while maintaining high operational fidelity. In the experiment, the fidelity of the entangled state was an impressive 84–88%. Moreover, for the first time, scientists managed to close the "detection loophole" for a fully distributed multi-component quantum state. The results also confirmed the violation of the Mermin inequality—one of the strictest tests for the presence of true quantum correlations.
A look into the future
This 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 now the architecture has been expanded to three full nodes. Although the technology is still far from commercial application, such experiments are the building blocks for future distributed quantum computers, secure communication networks, and, ultimately, the quantum internet.
My expert perspective: This result is not just a scientific sensation, but a clear signal to the market. The modular approach to quantum computing is ceasing to be a theory and becoming an engineering reality. If the pace of progress continues, we could see the first prototypes of distributed quantum networks for specific tasks within the next 5–7 years. Investors and technology companies should closely monitor the development of this field—it will become one of the main drivers of the next technological cycle.