
Back to the future: Chinese team's record transmission lays ground for quantum internet
Chinese scientists have set a transmission record in quantum secure direct communication, which brings the technology to the internet dial-up speed of the 1990s and sets the stage for a future quantum internet.
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The team's new quasi-quantum secure direct communication (QSDC) protocol set both a transmission and a distance world record with a transmission rate of 2.38 kilobits per second (kbps) over 104.8km (65 miles) of standard telecommunications optical fibre.
This speed allows for the secure transmission of text, voice, and image files in quantum states, making it potentially useful for securely sending small amounts of sensitive information – such as financial data or information vital for national security.
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'This system paved the way for the practical application of QSDC and offers a unique method to detect eavesdropping online, which is crucial in certain circumstances,' the team wrote in a paper published in the peer-reviewed journal Science Advances on February 21.
Inventor of the QSDC technology Long Guilu, a physics professor at Tsinghua University and vice-president of the Beijing Academy of Quantum Information Sciences, said the protocol could also be used for constructing a quantum internet.
Unlike the classical internet, in which information is transmitted as bits, a quantum internet would aim to enhance internet capabilities and security by leveraging quantum bits, or qubits, and quantum phenomena to achieve ultra-secure connection.
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'Prototype quantum internet based on this protocol has already been built in our lab,' Long said.
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