An international team of researchers from the Austrian Academy of Sciences (ÖAW) and the University of Vienna have established a quantum encrypted connection between Malta and Sicily (192 km) via a conventional submarine telecommunications cable using entangled light particles.
This record distance is being viewed as a further step in the development of a secure quantum internet. The connection was maintained over this long distance without further stabilization over a period of more than six hours.
“This total distance of 192 kilometres is a new record for the method of producing quantum keys through polarisation-entangled light particles over longer distances on Earth. In this test setup, the transmission speed reached four bits per second” the researchers said.
The team published its results in Nature Quantum Information.