Breakthrough in Quantum Networks: Scientists Entangle Three Remote Atomic Qubits for the First Time
The world of quantum technologies has witnessed a significant step forward. A research group, combining the efforts of Duke University and the company IonQ, has announced the creation of the first fully distributed three-node quantum network operating on the basis of individual atomic qubits. This achievement marks a transition from simple two-point entanglement to a more complex, multi-component architecture.
During the experiment, specialists managed to form a so-called Greenberger-Horne-Zeilinger state (GHZ state) between three remote quantum nodes. The key feature of this breakthrough is that communication between the nodes occurs via photonic channels, which is a necessary condition for creating scalable quantum networks.
Why This Changes the Game
The main problem with modern quantum computers is scaling. Creating a single giant quantum processor involves colossal technical difficulties, including a high error rate and hardware limitations. The modular approach, where the network consists of many interconnected quantum nodes, is seen as the most promising path to creating powerful quantum computing systems. This experiment is direct proof of the viability of such an approach at the level of individual atoms.
Unlike previous work, where entanglement was demonstrated on other physical platforms, this research has achieved three-way entanglement for individual atomic qubits for the first time. This is critically important because such qubits can be independently controlled, read, and, most importantly, scaled to build full-fledged computing machines.
Technical Details and Prospects
The results of the experiment are impressive. The fidelity of the obtained entangled state ranged from 84% to 88%. Moreover, scientists managed for the first time to close the "detection loophole" for a fully distributed multi-component quantum state. Additional confirmation of the authenticity of the quantum correlations was the violation of the Mermin inequality — one of the most stringent tests in quantum physics.
This success is a natural stage in the work of the IonQ team, which had previously demonstrated entanglement between two remote ion systems. Now the architecture has been expanded to three full-fledged nodes. Although commercial application of the technology is still far off, such experiments lay the foundation for future distributed quantum computers, absolutely secure communication networks, and, ultimately, the quantum internet.
Expert Opinion: Achieving three-way entanglement on individual atomic qubits is not just a scientific curiosity, but a critical engineering step. It proves that we can build quantum networks not on paper, but in reality, using controllable and scalable elements. It is precisely these "building blocks" that will ultimately make it possible to create a quantum internet capable of solving tasks beyond the reach of even the most powerful classical supercomputers.