What is quantum space

Abstraction in the quantum space

A system with one billion particles is no longer conceivable for normal mortals. Not to mention a billion such systems. And even then you have not yet reached the scale that Ronny Thomale is concerned with. It is once again larger by a factor of ten thousand.

"We try to change the behavior of 1023 Predict particles and develop models for their interactions, ”he says. Ronny Thomale has been the new professor at the Chair for Theoretical Physics at the University of Würzburg since this semester. At the age of 31, he is currently the youngest professor at the university; only in medicine is there a female professor who is even younger.

Research on superconductors

"The theoretical description of strongly correlated electron states": This is how Ronny Thomale describes his research area. “Strongly correlated electron states” can be found in superconductors, for example. These materials are currently the great hope of the energy industry: their electrical resistance drops to zero below a certain temperature. For example, electricity could circulate in a ring-shaped superconductor for a long time without loss - a superconductor would therefore be an ideal storage medium. And with cables made of this material, electricity could be transported over any length of distance without losses - if need be, even from a solar power plant in the desert to a Würzburg stove.

Looking for the right combination of materials

However, the currently known superconductors have a serious disadvantage: They only show this property at very low temperatures - the current record is minus 135 degrees Celsius. But that is about to change: “Our research on unconventional superconductors aims to identify a material that ideally works at room temperature,” says Thomale.

Which materials could be suitable candidates? How do atoms of different elements have to be combined for these unusual effects to occur? Thomale ponders such questions. He tries to simplify and abstract the relationships in real systems as much as possible until a model is available that other physicists can test for its practical suitability in experiments.

Well-founded hope for the quantum computer

His work not only helps in the development of potential superconductors. A quantum computer also works on the basis of the effects with which Thomale is concerned. "A computer that stores, manipulates and reads information in the form of quantum bits would be significantly faster than a conventional device for certain computing problems," he says. In his opinion, the progress made by science in this area so far allows “reasonable hope” that functioning devices will appear on the market in the future.

The ERC Starting Grant

So-called “topological quantum phases” form a basis for developments such as superconductors and quantum computers. They are also the focus of Ronny Thomale's new project, which the European Commission has now approved. "Topolectrics - Emergence of Topological Phases": This is the title under which Thomale will continue and intensify his research over the next five years. He will receive around 1.3 million euros from the EU's pots for this. “For a theorist, this is significant financial support. This allows me and my group to pursue several lines of ideas at the same time, ”he says. With the help of the Starting Grant, he plans to build a group that will be visible around the world.

Berkeley, Princeton, Stanford and Lausanne: these were the names of Ronny Thomales stations before he was appointed to the University of Würzburg. From his point of view, this change was consistent. “Würzburg physics has a very good reputation, especially when it comes to my research area,” he says. After all, the discoverer of the quantum Hall effect, Nobel laureate Klaus von Klitzing, spent eleven years researching in Würzburg, creating the basis for his discovery. This effect established the foundation for the field of research with which Thomale is concerned.

Topological isolators

What is even more important: one of the currently leading physicists in the field of topological insulators, the experimental physicist Laurens Molenkamp, ​​teaches and researches at the University of Würzburg. In 2007 he and his research group showed that topological insulators only conduct electricity on their surface, but not inside. In thin layers of some of these materials, the edge current consists of exactly two channels in which individual electrons move. The direction of flow in the two channels is opposite, as is the spin alignment of the electrons. This behavior is called the quantum spin Hall effect, based on the quantum Hall effect.

Molenkamp and his American colleagues Charles Kane and Shoucheng Zhang have already received several awards for the theoretical prediction of topological insulators and their experimental confirmation.

Understanding the microscopic processes in such topological phases better: Ronny Thomale wants to contribute to this with his work. With his models he wants to explain how such phases arise and how they are most likely to be reached. In this way, he wants to provide the experimental physicists with the “blueprint” for materials with which they can make the dream of a quantum computer and superconductivity come true at room temperature. Thomale actually sees the fundamental motivation for his work elsewhere: "The knowledge that arises in the process of my physical research is one of the greatest joys of my life."

To person

Ronny Thomale was born in Münster in 1982; He grew up in Karlsruhe. At the university there he studied physics with a minor in computer science. Equipped with a DAAD research grant, he spent six months at UC Berkeley. In 2008 Thomale received his doctorate with a thesis on "Fractional Statistics in low-dimensional spin systems". Further stations were Princeton and the Stanford Institute for Theoretical Physics. Before moving to Würzburg, Thomale was assistant professor at the Ecole Polytechnique Fédérale de Lausanne. Since September 2013 he has been a professor at the Institute for Theoretical Physics I at the University of Würzburg.


Prof. Dr. Ronny Thomale, T (0931) 31-85712, [email protected]