Thought Leadership
Confidential patient data, bank details and highly sensitive government and military information must be increasingly protected against eavesdropping and hacking. The necessary basis for this is provided by quantum physics, which goes far beyond conventional mathematical techniques for encryption.
This is because the unimaginably tiny world of quanta has its own rules: For example, the state of a particle often changes as soon as it is observed. This is ideal for quantum cryptography.
Light-conducting core thinner than a hair
The Karlsruhe Institute of Technology (KIT) wants to advance the research and development of quantum networks. To this end, the university has had a 20-kilometre-long fiber optic test track laid between specially equipped laboratories on the South and North Campus.
According to a spokesperson, it has a diameter of 125 micrometers, i.e. just over 0.01 centimeters. The light-conducting core is only around 9 micrometers thick. By comparison, a human hair is around 60 micrometers thick, according to the data.
According to the KIT, so-called quantum keys, which are crucial for tap-proof communication, can be transmitted via the test track. And this, in turn, is of central importance for a networked society.
Threat from quantum computers underestimated
“Quantum communication is a key technology for future security in data transmission,” says the Federal Ministry of Education and Research. “It can protect against attacks using both modern computers and powerful quantum computers.”
The background to this is that quantum computers work very differently to traditional computers – namely with so-called qubits. Like a bit in a classical computer, a qubit can be in the state 1 or 0 – but also simultaneously in the state 1 and 0 or in a theoretically infinite number of states in between.
Quantum computers are therefore good at solving problems that are extremely difficult for classical computers. For example, they can better simulate complex chemical systems or calculate optimal routes more quickly.
Again, this makes it relatively easy to break previous encryptions that are based on mathematical assumptions. According to the German Federal Office for Information Security (BSI), the threat to information security posed by quantum computers is widely underestimated.
Research for the future quantum internet
Chancellor Olaf Scholz (SPD) emphasized the importance of such technologies in the autumn in Ehningen near Stuttgart at the opening of the first quantum computing center of the US technology group IBM in Europe. In such areas, he said, we should not be dependent on other countries.
Over time, KIT would like to expand the new test track into a quantum network. With this help, scientists will be able to research elements of the future quantum internet.
The project is a central infrastructure of the “Chem4Quant” Cluster of Excellence initiative. Researchers from KIT and the universities of Ulm and Stuttgart want to develop novel qubit materials and initial components for the quantum internet. “With chemically precisely definable quantum architectures, atomically precise material structures and their quantum properties can be specifically planned,” they say. For example, qubits could be positioned in electrical components with a precision below the nanometer range.
Important breakthroughs achieved
The system is also important for research into so-called quantum repeaters. These are intended to enable the secure transmission of information over long distances – similar to WLAN repeaters.
The Federal Ministry of Education and Research is funding a project launched at the beginning of January with a total of 20 million euros over three years. According to Saarland University, 42 research institutions and companies are working together to develop the basic building blocks of a quantum network structure based on quantum repeaters.
According to the BSI, the main challenge with quantum computers is their susceptibility to errors: “Quantum systems are very sensitive to interference and therefore require complex error correction, which is known as quantum error correction.” Recently, there have been a wealth of developments in this area that could make a cryptanalytically relevant quantum computer possible in just under ten years.
dpa
