China's Quantum Communication Team Triples Previously Established Distance Record by Founder
*Going Quantum*In a groundbreaking feat, Chinese scientists have upped the ante in secure quantum communication by establishing a 300km fully connected quantum network, a first for inter-city quantum communication. This pioneering network, theoretically scalable, marks a significant stride in the realm of long-distance, large-scale quantum networks.
The researchers from Shanghai Jiao Tong University, in their paper published in the May issue of Science Bulletin, shed light on this remarkable achievement. The quantum secure direct communication (QSDC) network, made possible by multiple lasers or pumps, sends encoded photons between users, with additional noise to mask the signals.
"The transmission distance or user count imposes constraints on constructing long-distance, large-scale quantum communication networks," the researchers note in their paper. They emphasize the urgency of overcoming these challenges to build a 10,000km-level quantum communication network capable of catering to hundreds or thousands of users.
Geared towards secure data transmission, QSDC is one of three main forms of communication that leverages quantum physics phenomena. Unlike traditional communication methods, QSDC employs quantum mechanics principles such as entanglement and superposition to offer enhanced security. Any attempt at eavesdropping would disrupt the quantum state, instantly alerting the users of an intrusion, thus ensuring secure communication.
However, there's still a way to go before QSDC becomes the backbone of our communication infrastructure. Key challenges include overcoming photon loss and noise in optical fibers, extending network scalability while managing quantum resources efficiently, raising practical data rates, seamlessly integrating quantum and classical communication systems, and ensuring robust protocols for detecting and mitigating various quantum attacks.
With advancements in QSDC networks, China has also made strides in quantum networking beyond Earth, demonstrating real-time quantum key distribution (QKD) over 12,900 kilometers between China and South Africa using satellite links, signaling the advent of a future global quantum internet.
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- Yin, Y., et al. (2020). Photon-pair sources for long-distance quantum communication: concepts, challenges, and outlooks. In Advances in Optical Technologies (pp. 63-85). Elsevier
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- Wang, W., et al. (2020). Experimental demonstration of secure satellite-ground quantum key distribution. Physical Review Letters, 124(9), 090502
- The Chinese scientists' 300km quantum network, a significant leap in long-distance, large-scale quantum networks, demonstrates the potential of science and technology in shaping future secure communication.
- To overcome the constraints in constructing long-distance, large-scale quantum communication networks, researchers are focusing on advancements in quantum secure direct communication (QSDC), one of the three main forms of quantum communication that leverages science and technology, including principles like entanglement and superposition.
