Researchers at China’s Tsinghua University, the Beijing Academy of Quantum Information Sciences, and the North China University of Technology have laid the groundwork for a quantum Internet.
The team has developed a quasi-quantum secure direct communication (QSDC) protocol, which was able to send 2.38 kbps over 104.8 km (65 miles) of standard telecommunications optical fiber. That is both a transmission and a distance world record.
Unlike the classical internet, in which information is transmitted as bits, a quantum internet would use quantum bits, or qubits, and quantum phenomena to achieve ultra-secure connection. The quantum internet is based on quantum mechanical phenomena, such as superposition and entanglement, and implements quantum cryptographic protocols for safeguarding communication.
Quantum computers exist in the physical world, but a quantum internet is still theoretical. According to the China researchers, QSDC had been impractical to apply because it suffered large losses and had covered short communication distances. But the team solved the problem with a new one-way single photon quasi-QSDC protocol, meaning the photons flowed in one direction at a time to help reduce loss. It is classified as a quasi-QSDC protocol because it still involves the use of a key.
“This protocol enables the simultaneous transmission of information and key exchange using the same single photons and is robust against loss and error,” the team wrote.
Will the Chinese approach pave the way to practical quantum computing? Perhaps. One thing is for sure. With DOGE on the loose, it won’t happen in the US.