Accelerating developments in quantum technology – is Sweden keeping up?

Quantum technology is challenging our understanding of what is possible. By controlling and manipulating individual atoms, electrons and particles of light (photons), scientists can harness the fundamental principles of quantum mechanics to revolutionise the way we process information, measure, communicate and simulate complex systems.

Quantum technology falls into four areas

The technology is usually divided into four main areas: quantum computing, quantum simulators, quantum communications and quantum sensors - with applications ranging from advanced materials and energy efficiency to new ways of handling information. 

In quantum computing, for example, "quantum supremacy" has become a goal everyone is striving for; a paradigm shift where a quantum computer will, for the first time, perform a calculation that a classical computer cannot perform in a reasonable amount of time.

"Developments in quantum technology are very exciting to follow. On the one hand, it's groundbreaking technology, and on the other, quantum physics is so fantastically exciting, with phenomena we don't see in the classical world."

"There is also a lot of drama – claims of 'quantum supremacy' are made, other researchers try to refute them, while the goal is constantly being pushed forward," says Linda Johansson, Director of Nanotechnology at RISE.

It may sound like science fiction, but the fact is that first-generation quantum technology is already all around us - in GPS, lasers and atomic clocks, for example. Quantum computers are mainly used in research.

"Some types of calculations, especially in quantum chemistry and molecular simulation, can be done much more efficiently on a quantum computer. For example, drug development and the design of new materials can be revolutionised in ways that classical computers cannot," says Linda Johansson.

A strategic research area for Sweden

Second-generation quantum technology is now attracting the world's attention. In the research bill presented in December 2024, the Swedish government highlighted quantum technology as a strategic research area.

"It is believed that quantum computers could become important in chemistry, materials science, life sciences, logistics and finance. "A classic example is the travelling salesman problem – optimising routes, which is very difficult for classical computers, but where quantum computers can make great progress," says Linda Johansson.

"The travelling salesman is a classic optimisation problem where a salesman has to find the shortest route between several cities. Such problems are difficult for classical computers because the number of possible solutions grows exponentially. Thanks to superposition and quantum parallelism (see fact box), a quantum computer can process multiple solutions simultaneously and thus find the optimal path much faster."

Quantum computers will be used alongside supercomputers

However, quantum computers will not replace classical computers. Rather, they will be used alongside supercomputers in hybrid solutions, where the quantum computer performs specific calculations where it has an advantage. The possibilities are many, but it will be many years before they have a major impact on society as a whole.

A quantum computer needs an extremely stable and often very cold environment to operate - this is just one of many problems that need to be solved.

"Another major hurdle is that they are extremely sensitive and prone to miscalculation. This is why there is a lot of research into "error correction", i.e. how to correct the errors. "For quantum computers to become practical, advanced methods are needed to correct computational errors and reduce the error rate," says Linda Johansson.

Challenges with the technology

The technology itself poses challenges. For example, a quantum computer could break today's RSA-based encryption, which is virtually impossible for a classical computer to do.

Even if it is not yet possible, there is a risk that someone will collect encrypted information today in order to break it in the future.

"Therefore, we cannot wait to secure encryption. To meet this challenge, research is being carried out at RISE and elsewhere on post-quantum cryptography – algorithms that will withstand quantum computers – and quantum key distribution, which uses quantum technology to create completely secure encryption," says Linda Johansson.

Sweden has world-leading expertise in second-generation quantum technology, especially in superconducting quantum computers through WACQT (Wallenberg Centre for Quantum Technology). But other countries are ahead because they have made more concerted efforts.

"Other countries, such as Denmark, have built a strong ecosystem and managed to attract large companies. Sweden can learn a lot from them. We need to join forces between research institutes, universities and companies and invest in test beds and infrastructure. Small companies need support to scale up. RISE has an important role to play here," says Linda Johansson.

RISE has cutting-edge expertise in several areas related to quantum technology, such as standardisation, photonics, materials development, AI, fibre optics, quantum communication and algorithm development. The expertise covers both hardware and software, ranging from the development of quantum materials, quantum encryption and simulations to test and demonstration facilities for quantum technology.

Bridge between academia and industry

In early 2025, RISE won a pitch competition through the Quantum Sweden Innovation Platform (QSIP) to launch two projects to develop single-photon sources – one of which will be carried out in collaboration with researchers at Linköping University and start-ups PLT and Xtal Works.

"RISE acts as a bridge between academia and industry. We can help companies understand quantum technology, develop prototypes and drive innovation. We can also support governments, especially on issues such as quantum-secure encryption," says Linda Johansson.