Sun Jul 18 2021
Japan’s NICT researchers break records in quantum internet speeds.
Japan’s National Institute for Information & Communication Technology (NICT) was the setting in which researchers claim to have achieved a record-setting internet speed of 319 terabits per second (Tb/s) – completely smashing the previous record of 178 Tb/s.
The previous record was no small feat. It was set last year by a joint team of scientists in Japan and the UK by transmitting data along three fibre optic tubes rather than conventional copper wires.
That was back then.
The record-smasher speed used similar technology but with four cores, a sophisticated laser system and a bunch of rare earth materials in a lab that simulated a transmission distance of more than 3,000 km.
The system used wavelength-division multiplexing (WDM) technology to transmit data, which was beamed from a 552-channel comb laser fired at various wavelengths.
The data signal was then split into 552 channels and then sent down the four fibre optic cores.
The signal then travelled through 70km of optical fibre before being processed and amplified by novel fibre amplifiers doped with erbium and thulium. After this amplification it carried on its path, experiencing regular amplification process called Raman amplification.
We demonstrate the recirculating transmission of 552 x 25 GHz spaced channels covering >120 nm of S, C, and L-bands in a 125μm diameter, 4-core fibre, measuring a decoded throughput of 319 Tb/s at 3001 km.
The bandwidth was maintained over the 3,000km without any performance drop too! Which is good news on top of the fact that the technology used is compatible with existing infrastructure and can be upgraded relatively easily.
The researchers say their experiments demonstrate that it’s possible to translate "the information encoded in the circular polarisation of a laser beam" into the spin state of an electron caught in a quantum dot. The team was able to read the state of the electron and confirm the electron was in the correct spin state.
What does this breakthrough mean?
Further research towards the development of quantum internet will eventually make it possible to send and receive information in a quantum manner quickly and securely.
Sun Jul 18 2021