Quantum teleportation reaches a new level: three remote atomic qubits entangled for the first time
A team of researchers from Duke University, in collaboration with engineers from IonQ, has achieved a breakthrough in the field of quantum networks. They have successfully created, for the first time, a fully distributed three-node quantum network based on individual atomic qubits. The key achievement was the formation of the so-called Greenberger-Horne-Zeilinger (GHZ) state among three remote nodes connected by photonic channels.
Quantum entanglement is a phenomenon where multiple particles remain inextricably linked, regardless of the distance between them. A change in the state of one particle instantly affects the others, making this effect the foundation for future quantum networks and the quantum internet. Previously, scientists had demonstrated entanglement between two remote nodes, but achieving a three-node network on individual atomic qubits represents a fundamentally new step.
Why This Is a Turning Point
The main challenge for modern quantum computers is scaling. Building one giant quantum processor is extremely difficult due to error accumulation and hardware limitations. This is why the industry is betting on a modular architecture: instead of a single massive computer, a network of many quantum nodes connected by photons is created. This approach resembles the development of the classical internet, where computing resources are distributed across thousands of servers.
The new experiment is a practical step in this direction. The researchers showed that individual atomic memories can form a shared quantum state through photonic connections while maintaining high operational fidelity. During the experiment, the fidelity of the entangled state was 84–88%. Additionally, the scientists closed the so-called "detection loophole" for a fully distributed multi-component quantum state for the first time and confirmed the violation of the Mermin inequality, one of the key tests for the presence of genuine quantum correlations.
A Step Toward the Quantum Internet
This work continues a series of IonQ studies in the field of photonic quantum connections. Previously, the company had demonstrated entanglement between two remote ion systems, and now it has expanded the architecture to three full-fledged nodes. Although the technology is still far from commercial application, such experiments are crucial building blocks for future distributed quantum computers, secure communication networks, and, ultimately, the quantum internet.
Expert Opinion: This result moves the quantum network from the realm of theoretical research into the domain of engineering prototypes. The demonstration of three-node entanglement on individual atoms with high fidelity is a signal to the market: modular quantum systems are becoming a reality. For cryptography and blockchain infrastructure, this means that protection against quantum threats must be implemented today, not postponed until tomorrow.