Perhaps you are one of those who have been waiting for the quantum computer for several years, which we have been told is inevitable. Already at this stage, DTU associate professor Sven Karlsson is starting to look a little nervous because among his partners are AQT and IQM, two European companies that manufacture and sell quantum computers.

“It’s a common misconception that a quantum computer doesn’t exist yet. It already does, so we don’t have to wait. However, current quantum computers aren’t big enough yet, which clearly limits the complexity of calculations, but they exist and are used,” says Sven Karlsson.

An example is IBM’s quantum computers, which anyone can access over the Internet. It is also widely used in scientific laboratories, supercomputer centers, universities, etc. all over the world. quantum computers exist. They are also among the customers to whom AQT and IQM sell their products.

Until now, it has not been possible to build quantum computers with large numbers of quantum bits. Quantum bits are used to process information in a computer, so the small number of quantum bits limits the complexity of calculations a quantum computer can perform. This is why Sven Karlsson characterizes the current use as mostly experimental, giving an opportunity to play with and understand technology.

“The technical level of current quantum computers is somewhat similar to the early stage of our current computers. When they first appeared in the 1950s, they were limited in number and at that time were unable to perform larger calculations than any calculator can do today.”

However, there are examples of computation performed using a quantum computer. One of the calculations Sven Karlsson knew was made during the coronavirus pandemic. The Italian football league needed to know how best to plan matches so that the different football teams had as little contact with each other as possible to reduce the risk of contamination. Since air travel was prohibited, the distance for players also had to be limited.

“A quantum computer is well suited for the kind of computations that would take too much time for a traditional supercomputer. A quantum computer can explore many solutions at once and is therefore more efficient at such computations than a supercomputer,” says Sven Karlsson. Collaboration between Sven Karlsson and his colleagues at AQT and IQM includes developing the hardware and software needed to connect a quantum computer to supercomputers.

“The quantum computers of the future will initially be connected primarily to the relatively small number of high-performance supercomputer computing centers that exist worldwide. The centers have already built the infrastructure with the relevant qualifications to work with quantum computers, and Sven Karlsson said, “Today, a quantum computer costs around DKK 150 million. It costs money, so it’s a relatively large investment,” he says.

Quantum computing cannot replace supercomputers. Instead, it complements them and will be used for very specific calculations. A quantum computer would also not have its own user interface, but would have to be accessed via supercomputers.

Standardization

As a result of the current worldwide production of quantum computers, a large-scale standardization effort is underway. It contains standards for all the pieces of hardware and software that make up a quantum computer. We hope to avoid the inefficiencies we experience in other technological areas, such as using our mobile phone with a single charger.

“We want to develop common standards so that we can understand and use the different components that make up a quantum computer around the world in the same way. This needs to be done at this early stage so that we don’t risk individual countries or parts of the world setting different standards,” says Sven Karlsson.

Sven Karlsson leads a group of researchers and practitioners with deep experience and knowledge of quantum computers, who will come together in the coming years to create recognized standards that can be used in future manufacturing.