Pristupačnost
On the occasion of the 100th anniversary of the founding of quantum mechanics, the United Nations has declared 2025 the International Year of Quantum Science and Technology, emphasizing the critical importance of these increasingly relevant technologies for our society. With the rapid advancement of quantum technologies—especially quantum computers - the world has become aware that the realization of a quantum computer capable of compromising existing communication systems, such as RSA encryption, is now only a matter of time.
CroQCI: Croatia's Contribution to the European Quantum Network
To prepare for the so-called Q-Day, governments of the world's leading economies have adopted strategies to adapt their communication systems by developing quantum networks resistant to quantum computers, with security based on Quantum Key Distribution (QKD). In line with this, the European Union launched the EuroQCI initiative (European Quantum Communication Infrastructure) in 2023, aiming to establish a pan-European quantum communication network. Croatia is participating through the CroQCI project (Croatian Quantum Communication Infrastructure), involving FER (Faculty of Electrical Engineering and Computing), along with CARNET, IRB, OIV, FPZ, IF, SRCE, and UVNS.
FER Leads the Space Component: Optical Ground Station
FER is leading the space component of the CroQCI project, which aims to develop Croatia’s first Optical Ground Station (OGS) for quantum communication, enabling connection of the Croatian quantum network to other EU quantum nodes (which also have OGSs) via Eagle-1, the first European quantum communication satellite.
An optical ground station typically consists of a dome and a telescope (with a diameter of 80 cm or more), a satellite tracking system, a laser system for classical communication, adaptive optics to correct signal distortion, a quantum receiver, and single-photon detectors based on superconducting nanowires, which must be cooled to just a few kelvin.
“We are dealing with extremely sophisticated equipment that, on a macroscopic level, resembles an astronomical observatory, but is capable not only of tracking satellites in low Earth orbit with incredible speed and precision, but also of receiving a single photon—a quantum of the electromagnetic field—from a satellite, processing it, detecting it, and converting it into information that becomes part of a key used to secure communications,” said Mate Jagnjić, MSC, the project’s technical lead.
FER as a Center of Excellence
As quantum communication moves from the realm of academic curiosity to a critical technical prerequisite for secure communication in the era of quantum technology, training new generations of quantum communication engineers becomes essential. And to provide high-quality education, cutting-edge research and projects, supported by strong collaborations, are needed—something FER is actively pursuing.
“Croatia is actively participating in building the European quantum communication network, where the synergy of experts and scientists from multiple institutions is crucial. FER, as a center prominent in computer security, communication systems, and space technologies, offers a unique combination of expertise needed to make a leap in quantum communications. Our current focus is on acquiring sophisticated equipment needed for scientific research and building the knowledge base required to educate students—the future drivers of quantum technology development,” said project leader Assoc. Prof. Josip Vuković, PhD.
To celebrate the International Year of Quantum Science and Technology, FER has organized a series of popular science lectures by its scientists and researchers: