“I’ve enjoyed physics ever since primary school, and in grammar school I was in a class focused on maths and physics – although I was probably the only one there who was really into it,” says Jan Kuneš with a smile, recalling the early days of his now extensive career in the field of materials physics.
He has been working on the theoretical study of materials since earning his PhD at the Faculty of Mathematics and Physics at Charles University. “I remember the exact moment when we were being taught how magnetism is influenced by temperature. I found it fascinating that this could be captured and described mathematically. And I thought to myself – this is what I want to do.”
But the path to solid-state theory wasn’t a straightforward one. “In the Czech Republic, it’s still a relatively small field. Back when I was studying, most theorists worked at the Academy of Sciences and didn’t even teach at the faculty,” Kuneš explains. “When I first chose to study solid-state physics, the degree programme was focused on experimental work.” It wasn’t until Kuneš started working at the Czech Academy of Sciences as a doctoral student that he moved into theoretical modelling of material properties.
Measuring materials like degrees in beer
During his PhD, Jan Kuneš began working on magneto-optical effects – in other words, studying the magnetism of materials using optics. “It’s actually quite similar to how you measure the strength of beer,” he says with a smile. “You shine linearly polarised light through a 20-centimetre-long beaker full of beer and measure how much the plane of polarisation has rotated by the time the light exits the other side. A ten-degree beer rotates it by ten degrees. It’s all related to the concentration of sugars in the beer.”
In much the same way, the properties of magnetic materials can be measured – or in Kuneš’s case, calculated. Researchers can shine polarised light on them and analyse the reflection or use X-rays to see how the material responds. X-rays have the added advantage of distinguishing between individual elements in a substance, helping scientists identify which ones are responsible for its magnetic properties.
As a theorist, however, Kuneš doesn’t study materials in the lab. Instead, he tries to calculate their behaviour. “I usually start with the crystal structure of a material and try to calculate its properties. Of course, these are simplified models – some work very well for certain types of materials, but for many others they don’t. That’s where there’s room for improvement, or even for creating entirely new mathematical models.”
Using theoretical calculations, Jan Kuneš tries to estimate things like instabilities in a material, determine why it becomes magnetic and at what temperature. Simplified models that can describe trends in materials with certain compositions are especially important – they allow theorists to predict how a material might behave under specific external conditions and how it could be modified to adjust a particular property as needed.
“In Brno, I’ve come back a bit to what I was doing twenty years ago – only now I’m working with different materials and using more advanced computational methods,” Kuneš explains. “And recently, we’ve also started exploring something called altermagnetism.” This is the focus of his current work at the Faculty of Science, supported by the MUNI Award in Science and Humanities.
Between Vienna and Brno
The physics professor brings with him a wealth of international experience. After completing his PhD, he took a postdoctoral position at the University of California, where he spent three years. “Not only is California a pleasant place to live, but it was incredibly valuable for me to experience the American approach to research – which is quite different from what we’re used to here. In the Czech Republic, a lot of people keep working on the same topic they started with in their master’s thesis, and in my view, that often wastes their potential. In the US, it’s completely normal for researchers to start fresh – sometimes with entirely different topics.”
He later received a Humboldt Fellowship to work at the University of Augsburg in Bavaria, where he stayed for four years. After a brief return to the Academy of Sciences in Prague, he then spent seven years at the Technical University of Vienna before moving to Brno.
“At one point, it looked like we’d settle in Vienna for good,” says Kuneš, “but then a few different reasons led me to start looking for something new. I wanted to try a different path, and I also didn’t want my daughters to lose touch with the Czech Republic. My wife is Polish, so Czech is actually their third language,” he explains, speaking about his decision to apply for a position at Masaryk University.
He first heard about the MASH grant from a colleague at the Faculty of Science, and since he liked the proximity to Vienna and the Austrian Alps, he decided to apply – and succeeded.
Even a large MU grant has its limits
Kuneš appreciates the generous amount awarded by the MUNI Award in Science and Humanities, which provides five million Czech crowns annually. “With this, I can pay more people than with two grants in Austria. But what’s very restrictive is the requirement to report and settle the budget year by year, with only five percent of the planned annual funding allowed to be carried over to the next year. Considering how complicated, unpredictable, and time-consuming it is to bring high-quality postdocs from abroad, this can lead to wasted money – or worse, to lowering the standards for team members.”
Having extensive experience with various international grants, including the prestigious ERC, Kuneš points out that those grants – as well as German and Austrian ones – provide funding for four or five years, allowing researchers to spend the money as needed during that period.
“In the Czech Republic, this is a general problem with all grants, and it’s similar with labour law conditions. Because of various compensation rules for holidays and so on, you can’t really predict how much a particular person will cost over the course of a project. This is quite a unique concept globally. In the United States, for example, salaries are fixed annually, and a proportional amount is paid out each month, with no further complications. In neighbouring countries, there are standardised salary scales that specify exactly how much a doctoral student or postdoc costs per year. The advantage is that if inflation causes those scales to change, the grant provider automatically increases the funding,” Kuneš explains, describing another pitfall of Czech regulations. He is also critical of how overhead costs are determined and used, especially for paying senior staff, which reduces the funds available to build a strong team.
The goal? Quality people in postdoc positions
Administrative hurdles aside, Jan Kuneš has been focused over the past year on building a strong team. “Having quality people in postdoc positions is my ongoing goal. Recently, I’ve also become interested in a physics question about how the orbital moment is transferred from electrons to the lattice – something I’d really like to understand. For a scientist, these are the kinds of things that bring real satisfaction when you figure them out,” he says with a smile.
But what he definitely hopes to achieve in the near future is to contribute to building and developing a community of experts in solid-state theory across the wider region.