In conversation with Nicolas Kurz

What exactly is your doctoral project and what is so promising about it?

My doctorate is part of a large research project that aims to improve micro-acoustic high frequency filters. Everyone uses such filters on a daily basis during every form of wireless communication, for example while surfing the web or while calling someone. These filters use a piezoelectric material which sets the maximum bandwidth of the filter. The bandwidth, on the other hand, defines, among other things, how fast data can be transmitted. Considering that we want an increasingly faster internet connection, we require a much larger data rate and thus a much larger bandwidth, which is impossible to achieve with current electronic components. Therefore, a new material system is required for the next mobile radio standard 5G and that is what motivates my research.

For this purpose, I study thin layered aluminum scandium nitride and its pyroelectric characteristics. The striking qualities of this class of materials include piezoelectric properties and spontaneous polarization. This results in a consistent magnetic field without any external influence. These rare characteristics make it a promising new material system for the next generation of high frequency filters.

How did you come up with your topic?

I became aware of IAF during my college years at the KIT (Karlsruhe Institute of Technology). I visited a lecture held by Dr. Martin Walther, who also works at IAF, and at the end of the term we had an excursion to IAF. Their work immediately caught my attention, which is why I applied for my PhD at the institute after I finished my Master’s Degree in Physics. They proposed the topic to me, which originally was a project by the university of Freiburg. Therefore, I am actually enrolled at the university, but my workday is like anyone else’s at the institute, thanks to the great cooperation between IAF and the university.

What are the benefits of the cooperation between the IAF and the university?

I am already in the third year of my doctoral program and therefore almost finished. During the first two years I was exclusively at IAF. I was fully integrated and I could access all the resources of the institute. At the moment, however, I spend more and more time at the university, which is why I can evaluate quite well what kind of benefits the cooperation brings:

Fraunhofer IAF is very well equipped. The technical possibilities, especially of material production, exceed the university’s by far. Furthermore, the know-how in the specialized field of semiconductor materials is higher. The university, on the other side, has a much higher license pool due to its academic orientation. Thanks to my dual doctoral position, I can benefit from both, which is just perfect.

What do you plan on doing after you finish your doctoral degree?

I have no specific plan yet. I tend towards working in industry to experience this side as well. But who knows what the future holds and if I don’t end up at the IAF again, because I thoroughly enjoy working here.

Which advice would you give to a student who plans on pursuing a PhD?

You really don’t know what you get yourself into! I did not expect it to be that difficult and that it would require such a high level of stamina. Therefore, I would encourage students to assess themselves whether they really possess enough perseverance for the task. Furthermore, they need the ability to adjust quickly and to handle problems creatively.

What do you particularly appreciate about Freiburg and its surroundings?

I especially like the size. Everything is easy to reach by bike and it is neither too small nor too big. Furthermore, I like the people and the atmosphere around here.

What has been your personal highlight at Fraunhofer IAF?

I can’t recall ›the‹ highlight. But there are several small highlights every now and then. To witness how the project develops and keeps on making progress in spite of all obstacles is simply amazing. Every project milestone is a highlight to me.

How would you describe Fraunhofer IAF briefly in three words?

I think it is very difficult to describe IAF in only three words… But I have a good comparison: Actually, IAF is like a Hidden Champion. Even though it is only a medium-sized institute, with approximately 300 employees, it conducts cutting-edge research on a world-class level. As far as I know, IAF is ›the‹ institute in certain areas worldwide. This is easily overlooked, since it is such a specialized scientific field. Nevertheless, Fraunhofer IAF offers top-level research in a close environment.

Nicolas Kurz does his doctorate in the field of piezoelectric at Fraunhofer IAF and at the Department of Sustainable Systems Engineering INATECH at the University of Freiburg since 2016. Formerly he obtained his Bachelor’s and Master’s in Physics at the Karlsruhe Institute of Technology KIT.