STA, 5 August 2021 - The first ever public demonstration of fully encrypted quantum communication between Italy, Slovenia and Croatia took place during the meeting of G20 digital economy ministers in Trieste on Thursday.
It was the first time in history that fully quantum encrypted communication was made possible by means of optical fibres connecting three nodes, in Trieste, Ljubljana and Rijeka.
In Ljubljana, the event was held at the Faculty of Mathematics and Physics (FMF), whose dean Anton Ramšak noted that quantum communication would allow what have so far been unattainable levels of communication security.
"Comparing the security of encryption methods established so far and quantum communication is like comparing bows and arrows with guns," Ramšak illustrated.
The technology uses quantum keys, sequences of random numbers established remotely through exchange of individual photons of light.
5. 8. je potekala prva javna demonstracija medvladne kvantne komunikacije. Prvič v zgodovini je bil omogočen povsem kvantno šifrirani prenos med vozlišči 3 držav (Trst, Ljubljana in Reka). Sodelovali so tudi fiziki @FMF_UL, prof. dr. Rainer Kaltenbaek in prof. dr. Anton Ramšak. pic.twitter.com/3eNTiSSLq7
— FMF UL (@FMF_UL) August 6, 2021
The exchange protocol is based on quantum mechanics and if anyone tried to intercept the key, they would leave behind a trace that would alert those involved in communication and allow them to respond immediately.
In all other established technologies of information transfer, a copy of the key may be intercepted and copied without leaving a trace.
The quantum communication was tested by FMF physicists Rainer Kaltenbaek and Anton Ramšak in cooperation with their colleagues at the University of Trieste's Department of Physics and the National Research Council of Italy and Croatian physicists from the Ruđer Bošković Institute.
In his address, Kaltenbaek noted that Europe pioneered the field as early as 2012, but since the relevant institutions had not been willing to provide sufficient financial support, it was larger countries, mainly China which later took the initiative in implementing the technology.
Today's demonstration was also important in the context of the future European quantum communication infrastructure (EuroQCI), which is being promoted by the 27 EU member countries and the European Commission with the support of the European Space Agency.
The event depended on technical support of the link between Trieste and the FMF in Ljubljana via Postojna that was made possible by the telecommunications provider Telekom Slovenije through its modern network of optical links by means of dark fibres.
The test was the first ever application of quantum laws of nature outside science labs with the purpose of establishing fully secure communication.
After addresses by keynote speakers, a short concert was performed by musicians from the Giuseppe Tartini State Conservatory of Trieste and the academies of music in Ljubljana and Zagreb using the breakthrough quantum communication technology.
