“If you’re in a certain position, you should step forward”

Ms Moselund, you joined PSI on 1 February as head of the Laboratory for Nano and Quantum Technologies (LNQ), another new addition to the institute. Is that something special for you?

Kirsten Moselund: Yes, and I think that’s actually an ideal solution – it means we’re all new to the laboratory. I am just another member of the team that will be working together to build an exciting new venture at LNQ. Obviously we have to follow certain guidelines and we must ensure our work is relevant for PSI. But at the same time we also have a good degree of freedom.

You’ve been based in Switzerland since finishing your PhD, but you’re originally from Denmark. How did that come about?

I studied energy engineering in Denmark, but soon discovered that I was most interested in microelectronics, an area of solid-state physics. My first visit to Switzerland was as part of an Erasmus exchange. Back then I only had one afternoon to decide whether to study in Lausanne or go to Toulouse, in France. Lausanne looked so pretty in the photos that I made a spontaneous decision to go there. So I spent a year studying at the École polytechnique fédérale in Lausanne (EPFL). Once I graduated, I deliberately chose to go back there for my PhD.

Then you stayed in Switzerland after completing your doctorate?

Yes, because good job opportunities came up in Switzerland both for me and for my husband, who is also Danish. I started with IBM, first as a postdoc assistant and was soon employed as a full-time researcher. Switzerland has since become our home in every sense: our two children were born here and we now all have Swiss citizenship. Incidentally, when you work in research I think it’s easier to have children than it is in many other careers.

Really? How do you reckon that?

In some respects, research is more of a lifestyle than a profession. I might come up with new ideas just as easily while walking through the forest as sitting in the office. So sometimes you may be thinking things over during the evening or at weekends. Conversely, people are quite understanding if you occasionally need to leave work early during the week or you have to work from home if your own child is sick. Furthermore, I’ve always been able to work part-time in research. At IBM, my position was for 80% employment from the very start – even before we had kids. I love painting, and wanted to have time for this hobby. People told me at the time: “It’s still OK to work part-time if you’re a postdoc, but not later on in your career.” But in fact it never became a problem later, despite all the different career moves. Even in my most recent management role, I only worked 90% of the time, and now with my dual role at PSI and EFPL I still have a 90% employment contract overall. So I’m at home for my children on Wednesday afternoons, which is especially important for me.

So you would recommend working part-time?

For me personally, working part-time sets a clear boundary: I’m not available on a certain afternoon – unless something really is important. Working part-time is definitely not the universal solution for all, but I think it should be possible for everyone without having to compromise their career. By the way: in Denmark it’s taken for granted that couples share childcare duties equally while both young parents are free to pursue their own careers. So that was a given to me and my husband. I only found it a little odd that it wasn’t self-evident in my work environment. When I announced I was pregnant, someone at work commented: “Congratulations! But it’s a shame you’ll be leaving us”. It was as if that were the only possible progression.

Would you like to be a role model for young parents, showing that things can be different?

Definitely. Two things have always been clear to me: a child’s relationship with their father is just as important as with their mother. And secondly, no one should have to choose between career or family. That’s why I think that if you are in a certain position, you shouldn’t be afraid to step forward. I will often say: “I have to leave early today, I need to pick up my kids”. I always want to make it clear that it’s okay to have other priorities apart from a career.

Have you settled in well at PSI?

Yes, I’ve been given a very warm welcome. And leading LNQ is an opportunity for me to make a contribution to quantum computing, which is a new but rapidly evolving area of research.

Is this research area really so new? Haven’t a couple of big corporations already built their own quantum computer several years ago?

It’s important to understand that there are many, essentially different types of quantum computers. It starts with the different types of quantum bits, or “qubits”. IBM, for example, uses superconducting qubits. Others work on the basis of ion traps and other arrangements. It’s not like conventional electronics, where nowadays there is virtually only one established type: CMOS logic, which is based on complementary metal-oxide semiconductors. By contrast, there is an entire ecosystem of qubits and quantum effects that can be utilised technically. And perhaps many of these could co-exist in future – that’s still not clear. Whatever the case, it’s still very open as to which platform will eventually come to dominate. And in the academic world I see more opportunities to pursue these myriad approaches. In a nutshell, we are now at a threshold in research where we can better understand the effects in quantum computing and begin to control and use them. And universities and research institutes are currently the best places to build the new foundations.

Your research interest includes nanophotonics as well. What is that, and how does it fit in with electronics?

In the technical jargon, photons are light particles. Nanophotonics means that we are researching extremely small elements that generate or detect light, and can therefore be integrated into electronic components, where they can be used to transmit information. In data transmission over long distances we’ve already made the transition: in the past telephony used to operate over copper wire, now fibre optic cables deliver broadband into the home far more efficiently. The question now facing us is: from which distance on does it make sense to transport information by light rather than electrons? Perhaps already for certain distances within a computer chip. That would then involve nanophotonics, because it would require extremely small light sources in the form of LEDs or lasers on a chip.

Is that also a step towards quantum computers?

Perhaps. At IBM I was involved in researching the integration of new materials on silicon platforms, because silicon-based electronics is currently the best researched and developed platform. Ongoing developments enable different components to be created – either for artificial intelligence, quantum computing or quantum sensing. So the applications are remarkably diverse. Here at PSI one of our research areas is quantum technologies based on ion traps. The output is in optical form, and so integrated phototonics is the next step in the development process.

You’re obviously excited about future technologies!

I used to work in the cleanroom every day and really loved it. Making and measuring things yourself, creating things with your own hands – I find that very rewarding. As laboratory head, I probably won’t spend as much time myself in the cleanroom now. But I am building up LNQ and supporting my staff in their daily experimental work. I am already looking forward to the additional cleanroom soon to open on Park Innovaare. I always look for the connection between fundamental research and practical application. I want to help make all the opportunities created by Park Innovaare attractive to start-ups. PSI is already very active in the area of technology transfer. I am looking forward to expanding these developments even further with the backing of our laboratory.