Q&A with nanophotonics expert Angelos Xomalis

Angelos Xomalis is an Associate Professor in NTNU’s Department of Electronic Systems.

Here he talks to science writer Kelly Oakes about his research plans, how he got to where he is today, and why he prefers not to be the smartest person in the room.

A man showing a circular object. Photo

What is your role at NTNU?

I joined NTNU in August this year as Associate Professor of Nanophotonics. Next semester, I will also teach the electromagnetism course in the Department of Electronic Systems.

Can you tell me a bit about your academic background?

A man examining an instrument in a lab. Photo
Photo: Eleni Perivolari

I’m originally from Greece, and I did my masters and undergraduate degree there in Crete, in the southern part of Europe. Then I moved to the University of Southampton in the UK for my PhD, which mostly focused on nanostructures that can control light for faster communications. Next, I moved to University of Cambridge, for a postdoc, and then to Switzerland, where I was a researcher at the Swiss Federal Laboratories for Materials Science and Technology. There, I worked on understanding the fundamental light-matter interactions in thin films in order to make better materials.

Can you sum up your research in a few words?

I’m creating materials that can twist, bend and focus light into tiny volumes.

How did you first get interested in these areas of research?

Since I was young, I’ve been interested in how nature can create surfaces that have beautiful colours. It fascinated me that nature can do this on demand, and can tune these properties precisely. For example, there are some animals that, depending on their environment, can squeeze nanostructures under the surface of their skin and this results in a different colour. Based on that, I started working on metamaterials and nanophotonics, specifically on surfaces that have tailored optical properties. And this is what I’m doing now.

What was your last paper about?

We were using molecular springs that can convert infrared light – that we cannot see – into visible light. The idea is that we want to use such molecules to create efficient radiation detectors.

Those detectors could be used in a variety of fields. For example, in astronomy, or to measure pollution and greenhouse gases – detecting specific molecular fingerprints with light. We want to detect them efficiently using detectors that are at room temperature. Existing technologies use cryogenic temperatures, so they’re extremely bulky and can be hard to use and inefficient.

Now I’m leading a research line here at NTNU that is going to investigate this further. So we’ll try to see what is the best platform for this that is cost effective, green, and works in a relatively small volume.

Why did you choose NTNU?

I realised very fast that people want to work with you here. That’s important to me because I take a lot of energy from the people around me. NTNU invests in brilliant minds, and they are open to new directions of research.

What collaborations do you have planned so far?

One project, with researchers from the Department of Mechanical Engineering, is 3D printing and how we can create fine coatings on nanostructures to enhance both the mechanics and the optics of the device. Another project, with researchers from the Department of Chemistry, is how we can control chemical reactions to make catalysis more efficient, but still sustainable.

Where will you be working within NTNU?

I just received Rector’s funding to establish a state of the art optics lab that can do advanced nanoscale spectroscopies. And we have Nanolab nearby, too, and this is where I’ll base my next research steps.

What do you have planned for your research?

I will have the great opportunity to have both a master’s and a PhD student here that will work on nanoscale spectroscopies. My long term plan is to do in-operando spectroscopy that can help us to understand how batteries really work, how chemical reactions work, and how we can make better radiation detectors. Currently, there are a lot of unclear, intangible mysteries, about how batteries really operate – there are still a lot of questions that are not yet answered.

What would you say motivates your work?

I like to meet bright people in the course of my work and listen very carefully to what they have to say. It’s exciting to not be the smartest person in the room, and to learn things every day.

What do you do in your spare time?

I like the outdoors, so when I was in Switzerland I worked on my hiking skills. In Norway, the mountains aren’t so high, but I do lots of running, swimming and sports. I find walking in nature empties your mind. I try to get physically tired, not just mentally tired, to have balance.

What would you have done if you hadn’t become a scientist?

I’ve always liked to tear things apart to see how they really work. I could probably do some kind of engineering, so I could work with my hands in a similar way to what I’m doing when I do spectroscopy with a microscope, but instead I’d be tearing apart trucks or other things.