Experts have for the first time created three-way entanglement of remote atomic qubits in a quantum network: a breakthrough toward modular computing
Researchers from Duke University and IonQ have taken a significant step in the development of quantum technologies, demonstrating for the first time a fully distributed three-node quantum network based on individual atomic qubits. In the experiment, the specialists managed to form a so-called three-party entangled state (Greenberger-Horne-Zeilinger state) between three remote quantum nodes connected via photonic channels.
The Essence of the Experiment
Quantum entanglement is a phenomenon where a change in the state of one particle instantly affects the state of others, regardless of the distance between them. Previously, scientists had demonstrated entanglement between two remote nodes, as well as three-node networks on other platforms, but this is the first time such a result has been achieved specifically for individual atomic qubits. These qubits can be independently controlled, read, and scaled, paving the way for the creation of complex computing systems.
Why This Matters for the Industry
The main challenge for modern quantum computers is scaling. Building a single large quantum processor involves enormous difficulties due to errors and hardware limitations. Many developers are betting on a modular architecture: instead of one giant computer, a network of many quantum nodes connected by photons is built. This approach resembles the development of the classical internet, where computing resources are distributed across servers.
In the experiment, the researchers achieved an entangled state fidelity of 84–88% and, for the first time, closed the so-called "detection loophole" for a fully distributed multi-component quantum state. The results also confirmed the violation of the Mermin inequality—one of the key tests proving the existence of genuine quantum correlations.
The Path to a Quantum Internet
This work continues a series of studies by the IonQ team in the field of photonic quantum connections. Previously, the company's specialists demonstrated entanglement between two remote ion systems, and now they have expanded the architecture to three full-fledged nodes. Although the technology is still far from commercial application, such experiments are critically important building blocks for future distributed quantum computers, secure communication networks, and the quantum internet.
My Expert Opinion: This breakthrough confirms that the modular approach to quantum computing is becoming a reality. For the crypto industry, this means that within 5-10 years, quantum-resistant networks and data protection could become the standard, rather than science fiction. However, practical cracking of existing cryptographic systems is still far off—current results only demonstrate fundamental principles, not ready-made solutions.