Kristel Michielsen

The physicist uses supercomputers to advance the development of quantum computers – primarily by simulating the way that quantum computers work on supercomputers.

Kristel Michielsen (Forschungszentrum Jülich/Ralf-Uwe Limbach)
Kristel Michielsen
Forschungszentrum Jülich/Ralf-Uwe Limbach

Testing and evaluating

Prof. Kristel Michielsen’s CV includes a world record: she and her team simulated a quantum computer with 48 qubits on supercomputers. Such simulations allow a quantum computer’s computational steps to be reproduced and its computational quality to be evaluated. In this way, she and her team checked the calculation that Google’s quantum processor Sycamore used to demonstrate quantum supremacy, for example.

The simulation programme used to do so, JUQCS-G, was co-developed by Michielsen. Known as an emulator, it can also be used to test algorithms that will run on quantum computers in the future. The development of such methods and models is one of the focal points of her working group.

“Developing quantum computers is like travelling in a hot air balloon. We are currently in the process of ascending. And we know that the balloon will go somewhere – we just don’t know the exact direction yet.”
Kristel Michielsen

Driving force

The Jülich expert is also working on connecting supercomputers with quantum computers that are already in operation. These hybrid systems aim to make the computing power of existing quantum systems usable for the first practical applications today. She is also a driving force behind the Jülich UNified Infrastructure for Quantum computing, or JUNIQ for short. The user infrastructure enables access to various quantum systems

For her research, Michielsen has received a Google Faculty Research Award and the Wim Nieuwpoort Award.

Quantum computing maturity

Together with Thomas Lippert, head of the Jülich Supercomputing Centre, Michielsen developed a scale that describes the maturity of quantum computing technology. The Technology Readiness Level of Quantum Computing Technology (QTRL) is based on NASA’s assessment of space technologies. The quantum computer scale ranges from level 1 (formulation of a theoretical framework) to level 9 (quantum computers exceed the power of conventional computers). Currently, Michielsen considers development to be at level 5: components have been integrated into a small quantum processor without error correction.

Selected projects

    Coupling of two quantum simulators with two European supercomputers, including Jülich’s supercomputer JUWELS
  • OpenSuperQ
    Construction of a European quantum computer with superconducting qubits


  • Institute for Advanced Simulation (IAS)
  • Jülich Supercomputing Centre (JSC)
Building 16.3 /
Room R 340
+49 2461/61-2524

Last Modified: 18.08.2022