At the beginning of 2022, Claude Monney became a full professor at the Faculty of Science and Medicine. He tells us what brought him here, about his research and about his teaching philosophy. Portrait of Claude Monney.

Q: You recently became a professor at Fribourg; what led you to choose our university?

"I am originally from Fribourg and I studied physics at the University of Fribourg. In fact, it is so difficult to get a teaching position in physics that, when I was younger, I never imagined I would be able to come back to my "alma mater" to settle down.

In practice, it's a mixture of opportunity and coincidence, as is often the case in life. I obtained a professorship from the Swiss National Science Foundation in 2018 and came to work in Fribourg with Prof. Philipp Aebi, who was my thesis supervisor 13 years earlier. Then, when he retired in 2020, I was chosen to succeed him. I am therefore very happy to be able to take over from him in my home canton."

Q: Tell us about your research. What is your research focus and what are your goals?

"My specialty is ultrafast spectroscopy of novel materials. In my laboratory, we use very short pulses of laser light to probe matter by photoemission. We expel electrons, which we analyse to reconstruct the electronic structure of the material. Our aim is to better understand the link between the macroscopic behaviour of matter, for example abnormal electrical resistivity, and the microscopic organisation of electrons and atoms.

When I joined the physics department, I brought in a new experimental approach: using a combination of several very short laser pulses, we excite materials with a first intense pulse and then probe them with a second weaker pulse. By playing with the time difference between the two pulses, we can follow the evolution of electrons and atoms on a very short time scale: less than a picosecond, or 10^-12 s!

One of my objectives is to create new ephemeral states of matter, known as out-of-equilibrium states, with physical properties never encountered at equilibrium. This kind of experiment is currently very promising for laying the foundations for the electronics of the future."

Q: Why did you choose physics as a career?

"As a college student, I was drawn to different paths of study, both in the natural sciences and in philosophy, for example. I remember that my choice of physics came from my interest in understanding the fundamental mechanisms of our universe, stimulated by the scientific magazines I subscribed to. During my studies at the physics department in Fribourg, I was captivated by solid state physics and exotic phenomena such as superconductivity and so I went in that direction afterwards."

Q: Do you remember your first experiment?

"My first experiment in physics was during my first year practicals at university. The first experiment, which involved atomic spectroscopy, was assigned to me at the very beginning of the semester and was related to a chapter of theory that would be covered at the very end of the year, the Bohr model of the atom. I didn't realise this. So I worked hard to understand this model and in the end had some pride in achieving it at the beginning of the first year..."

Q: What is your teaching philosophy? What message do you want to get across to students?

"It is not easy to teach physics at university, as students need a solid background in mathematics before they can appreciate the full depth of an equation or spot the fine details of a beautiful photoemission spectrum.

I therefore encourage students to persevere in their university studies and to appreciate these moments of discovery. What could be more stimulating than the first classes on general relativity or quantum mechanics?

During my lectures, I try to find a balance between mathematical formalism and presentation of experimental data. It is crucial to link the two as well as possible, and I love to spot the spark in the students' eyes when they succeed.