Chinese researchers test a 100-channel detector in a quantum network

Researchers at the Shanghai Institute of Microsystem and Information Technology in China built a single-photon detector with 100 channels and tested it in a prototype quantum network, Interesting Engineering reported. The prototype recorded communication fidelity above 90 percent, according to the outlet. The researchers ran the detector continuously for seven days.

During that test, the cryogenic chamber remained below 2.1K, a temperature close to the absolute-zero benchmark of 0K, the article said. It also reported that the detector’s channels achieved 80 percent detection efficiency and produced extremely few false positives, citing the researchers’ paper.

The article describes 32 channels as the standard limit for single-photon detectors and says that limiting channel numbers had been a workaround. The researchers’ design instead used 100 channels. The account does not identify the specific technical challenge behind that workaround or give a direct comparison of the new detector’s performance against a 32-channel device.

For a comparison intended to represent a more practical setting, the team built a quantum entanglement distribution network serving five users. The network contained 10 two-way quantum links, Interesting Engineering reported.

The article does not provide separate fidelity figures for individual users or links; the reported figure above 90 percent applies to communication fidelity in the prototype network.

The researchers’ reported results therefore combine a detector test with a network demonstration: continuous operation over seven days, chamber temperature below 2.1K, 80 percent detection efficiency, and communication fidelity above 90 percent.

The article says the work could open a path toward broadband quantum-based networks in China, but it does not report deployment of such a network or a timetable for one. The report identifies the researchers’ paper as the basis for the channel-performance and false-positive details, but does not name its authors or give the publication venue.

It also does not specify how the network’s fidelity was measured. The concrete next technical benchmarks in the account are the 100-channel detector’s measured performance and the five-user network with 10 two-way links.