“We are building the future of IT”

Prof. Kranzlmüller, what is behind the abbreviation Q-Exa?

Kranzlmüller: Q-Exa is the first German quantum demonstrator. It combines a 20-qubit processor based on superconducting circuits from IQM Quantum Computers with a classic high-performance computer. The Q in the abbreviation stands for quantum computing and the Exa for our future exascale computer, which we are currently procuring. This will then be the next generation of supercomputers at the LRZ. Our aim is to combine both technologies in such hybrid systems in such a way that they can play to their respective strengths.

Have you already tested the extent to which the conventional supercomputer is compatible with the IQM quantum processor—and how the performance changes?

Kranzlmüller: The basic assumption is that the performance of a quantum computer in selected applications far exceeds the computing power of conventional supercomputers. In reality, however, operating quantum computers is still very complex – and a system like ours with 20 qubits naturally doesn’t come close to exploiting the potential of quantum computing. Hence the idea of exploiting the strengths of the classic high-performance computer as far as possible and only handing over tasks to the quantum processor when it is superior. The integration is complex. That’s because it requires a program on the supercomputer that activates the quantum computer as soon as it can be assumed that a complex piece of code will accelerate the calculation in such a way that the overall hybrid system arrives at the solution faster and more accurately. Our test runs were successful and show that both technologies work together. We are now very excited to see how the hybrid system proves itself in everyday work and how we can use it to further develop quantum computing. We are building the future of IT.

Is there software that runs on both platforms, or is it developed within the project?

Kranzlmüller: We had to develop the software first, because there’s a lot of translation work between the binary system of classic IT and quantum computing. We invested a lot of time and expertise in that. The same applies to integrating both systems, which are actually stacked at the center in floors. As a research center, the LRZ has the task of integrating the latest research results into operating a data center. The quantum computers available today are not industrially produced, mature plug & play systems. They come directly from the physics lab and are maintenance-intensive.

The central processing units of the IQM system are based on superconducting circuits. Electrons are stimulated by microwave pulses to change their state and become entangled in order to carry out calculations. Such a setup is susceptible to so-called noise, which, like physical influences on the hardware, can lead to inaccuracies in calculations. The system therefore needs to be frequently calibrated. Our research not only distributes the computing tasks between the supercomputer and the quantum computer, but also investigates the possibility of automated calibration routines. We test them in the project and develop them further during operation. The aim is to demonstrate that integration into data center operations is feasible. At the same time, we are working on scaling the number of qubits. The follow-up project Euro-Q-Exa has already started and is aimed at this scaling and reducing noise.

What’s your approach?

Kranzlmüller: Here it’s also about very practical issues. The system is located in an area of our data center where not many people normally come and go. That’s different with the hybrid system – and we want to know at what intervals it needs maintenance, and whether it’s sensitive to electromagnetic interference, cell phone radiation or the vibrations caused by groups of visitors to the LRZ, for example. It’s all about how such a sensitive system behaves in the everyday life of a data center. The experience and expertise that we are now generating with regard to calibration will help us in the design of more powerful quantum computers in the future. We are taking a step-by-step approach and are working to the schedule set out in our roadmap.

What applications do you have in mind for the hybrid high-performance computer?

Kranzlmüller: We have early users in the project who are using the hybrid system to tackle complex issues in materials sciences and personalized medicine, including using digital twins of patients to investigate the mechanisms of diseases such as Alzheimer's, rheumatoid arthritis and various types of diabetes at the polygenic level. And because we’re based in Munich, we are also looking at issues from astrophysics. Here, too, the aim is to learn from the feedback of early adopters for the further scaling of quantum computers. It is also about the applications of quantum computing for which the topology of our hybrid system promises advantages. Basically, we have adopted an iterative approach so that together we can draw systematic conclusions from experiments and feedback for optimizing the systems.

The German Federal Ministry of Education and Research (BMBF) is providing funding of 40 million euros for Q-Exa. Will the computer also be available to external users?

Kranzlmüller: We are a scientific research institute and do not sell computing power. We are associated with EuroHPC JU (Joint Undertaking), with whom we are also driving forward the Euro-Q-Exa project. EuroHPC-JU is a legal and financial entity that has now signed agreements with six European data centers to host and operate hybrid EuroHPC-JU quantum computers. The aim is to build various platforms for quantum computing and hybrid quantum architectures and make them available to users throughout Europe on a cloud basis. Interested parties will be able to contact this partner in late fall to book slots on the system. Subsequent use has been agreed with the BMBF in order to provide interested companies with early access to quantum computing. The first inquiries have already been received, including from the automotive industry. That’s because many companies want to familiarize themselves with this future technology as early as possible so that they can play an active role in shaping this future.