Rainer Waser: „I have retained my childlike nature to this day“

He has founded various institutes, organised major conferences and gives lectures on artificial intelligence and philosophy: physical chemist Prof. Rainer Waser can certainly be described as a multi-talented individual. The most important milestones in his career include his appointment as full professor of electronic materials at RWTH Aachen University in 1992 and his appointment as director of the Electronic Materials Department at the Peter Grünberg Institute at Forschungszentrum Jülich in 1997. He has been retired since August 2024.

Mr Waser, you have had a very interesting career. Was this apparent from an early age?

You could certainly say that: even as a child, I was interested in everything – nature, technology, history, art and so on. I have retained this childlike nature to this day. When I was 16, I requested the free career information leaflets from the Federal Employment Agency: on university lecturers, physicists, chemists and electrical engineers. I was also interested in philosophy, but there was no brochure for that. From then on, it was clear: I wanted to become a university lecturer, almost regardless of the subject! I was particularly fascinated by the degree of freedom that came with it. That has always been important to me in life: that I can, to put it bluntly, do what I want – even if that is a bit of an exaggeration now, of course.

In 1992, you achieved your goal: you were appointed professor at RWTH Aachen University. How did that come about?

I studied chemistry at TU Darmstadt, specialising in physical chemistry and later electrochemistry. This allowed me to combine many of my interests. Before my intermediate diploma, I heard a radio report about the German National Academic Foundation: it said that 70 percent of the foundation's scholarship holders later become university lecturers. That naturally spurred me on: I approached a university lecturer who knew me and my academic achievements – and he successfully recommended me for the foundation. Later, the German National Academic Foundation enabled me to do a pre-doc stay at the University of Southampton, a Mecca for electrochemistry. Back at the Technical University of Darmstadt, I completed my doctoral thesis in electrochemistry and, at the same time – in my spare time, so to speak – developed circuit boards and software for an electronics company in Mainz. I was rewarded with hardware for this.

Even before my studies, I had been working intensively with Philips electronics kits, and after graduating, I spent eight years developing ceramics for electronics at Philips Research. In 1992, I was asked if I wanted to apply to succeed Professor Gottfried Arlt at RWTH Aachen University. I definitely wanted to! So I took over the professorship for electronic materials and established the field of electroceramics.

They also have close ties to Forschungszentrum Jülich: they took over as director of the Electronic Materials Department at what is now the Peter Grünberg Institute.

In 1994, Joachim Treuch, then Chairman of the Board of Directors of Forschungszentrum Jülich, announced that he and several colleagues would be visiting me in search of new topics. During the visit, I learned that a successor was being sought for the head of the Institute for Radiation Damage in Metals. My condition when I received the offer was that I wanted to retain my institute at RWTH Aachen University in its entirety. I took up my post in Jülich in 1997.

In addition, each institute director was appointed director of the internal programme ‘Physical Fundamentals of Information Technology’ for one year – myself included. It was precisely in 2001, when I was director there, that the Helmholtz Association (HGF) switched to programme-oriented funding. This enabled me to initiate my own HGF research programme, the ‘Fundamentals of Future Information Technology’, together with my colleagues. This was later expanded into a section of the Jülich-Aachen Research Alliance (JARA), where appointments are coordinated and major investments are discussed in advance. Another stroke of luck was the awarding of the Nobel Prize to Peter Grünberg in 2007: I was able to convince the then Executive Director Sebastian Schmidt to organise the departments according to research topics and restructure them into what is now the Peter Grünberg Institute.

Interdisciplinarity and ‘bridge building’ have driven you throughout your life. How does this manifest itself?

My most important scientific achievements are based on my interdisciplinary approach to problems. For example, the long-term ageing of electrical ceramics for capacitors manufactured by Phillips was never properly understood. As a physical chemist, it was perfectly normal for me to assume that ions could also migrate under these conditions – an idea that neither physicists nor chemists had come up with. I was able to elucidate this effect with colleagues from the Technical University of Karlsruhe, now KIT. I also played a pioneering role in the field of memristive materials, which can be switched with less energy than conventional electronic components. Although they had been known since the 1960s, the basic mechanism was not understood. I was able to resolve this dilemma in 2005. For this – and for other interdisciplinary activities – I received the Leibniz Prize in 2014.

In my opinion, you should always look at problems from different angles in order to make progress. This also applies to politics, which is why I read magazines from across the political spectrum. This gives you an overall picture from which you can form your own opinion. So I tend not to do things in a particularly conventional or conservative way. I also believe that you should have fun and do crazy things. But if you do a lot of crazy things, you're bound to make mistakes. I've made mistakes both in science and in my private life. Fortunately, I have what is perhaps a positive trait in that I completely forget many negative experiences.

In addition to the natural sciences, you are interested in philosophy. How much time did you have for that?

After writing a paper on music sociology with a philosophical background for a youth competition, reaching the European finals and winning one of the many second places, I decided to put philosophy aside for the time being. I simply didn't have the time. A few years ago, however, I rediscovered my other interests: since then, I have been re-engaging with philosophy and continuing my education in this field. I also enjoy giving lectures on artificial intelligence, which also touches on philosophy.