In a groundbreaking achievement, Chinese scientists have created the world’s first memory-memory entanglement in a multi-node quantum network spanning a metropolitan area. This milestone significantly extends the range of practical quantum networks from mere tens of meters to an impressive tens of kilometers, marking a three-order-of-magnitude enhancement.
The research team from the University of Science and Technology of China utilized three independent memory nodes, each equipped with an atomic ensemble quantum memory, along with a photonic server. The successful detection of a single photon by the photonic server heralds the generation of entanglement among the memory nodes, which are separated by distances of up to 12.5 kilometers.
“This accomplishment provides a robust foundation for the development of innovative quantum technologies, such as quantum computing and quantum-enhanced long baseline interferometry,” the researchers stated.
Quantum entanglement is a phenomenon where the quantum states of two or more particles become interconnected, so that the state of one particle cannot be described independently of the others, even when the particles are separated by large distances. This property is crucial for the creation of quantum networks, which promise ultra-secure communication and powerful computational capabilities.
The study, published this week in the journal Nature, demonstrates simultaneous generation of quantum entanglement between any two memory nodes in the network. Notably, the lifetime of the entangled states exceeds the duration required for round-trip communication between these nodes, a significant advancement for practical applications.
A peer reviewer from Nature commented, “This achievement marks a new stage in quantum internet research, paving the way for future large-scale quantum networks.”
The successful implementation of a multi-node quantum network over metropolitan distances is a pivotal step toward realizing a future quantum internet. It transitions quantum networking from two-node laboratory experiments to comprehensive multi-node setups on a larger scale, bringing us closer to practical and widespread quantum communication systems.
This breakthrough not only showcases China’s leading role in quantum technology research but also sets the stage for international collaborations and advancements in the field of quantum information science. As quantum technologies continue to evolve, they hold the potential to revolutionize computing, communication, and security on a global scale.
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Chinese scientists achieve multi-node entanglement in quantum network
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