What is the topic of your Ph.D. thesis?
The topic of my thesis is “Ion Interaction with Realistic Surfaces: Case Studies for Nuclear Fusion and Space Weathering Research”.
What is the focus of research?
The focus of my PhD research is the experimental study of different aspects of ion-solid interaction. In a nuclear fusion reactor, this is important to understand plasma-wall interaction. Ions that escape from the fusion plasma erode wall material, which will reduce their longevity. Hydrogen ions will also be implanted in the wall, which affects the efficiency of the reactor’s fuel usage. The hydrogen implantation and release behavior has been an important factor for the choice of reactor wall materials and is still extensively researched for ITER and future reactors.
What is the benefit for fusion research?
I have worked with tungsten and beryllium, which are both relevant for ITER’s wall panels and divertors. In order to single out some aspects of hydrogen interaction in such materials, I have performed experiments under controlled conditions at ion beam setups. This allows an easier understanding of the fundamental processes that occur here.
For both materials, several studies for erosion and hydrogen implantation exist, but it was a topic of my thesis to apply methods that allow additional measurements in the same vacuum environment. For example, in-situ ion beam analysis allows to observe the hydrogen content in the sample, while it is heated up – all done in the same clean vacuum environment. We can also observe mass changes of a target in real-time during the ion irradiation with a quartz microbalance. Such experiments can give more detailed insights into the underlying physical processes than many of the previously performed experiments.
What are the biggest challenges?
Especially ion implantation and thermal release are very complex and depend on many parameters. This represents a significant hurdle both in planning and interpreting experiments. Extensive knowledge about existing research and theoretic models are necessary to handle these challenges, which can seem overwhelming at the beginning.
Recently, the Covid-19 pandemic has emerged as an additional difficulty for my research, which is based on important international collaboration. Usually this is a big advantage, but now measurement campaigns had to be moved and working together in the same lab has become more complicated. However, handling unforeseen setbacks is an essential experience in research, so I am certain that we will also be able to manage this problem.
Which plans do you have for your future? What will you do in 5 years? Would you like to continue research or are you going to work in industry?
I have been a part of a scientific research group in some form for more than six years and I feel confident that I want to continue my career in science after finishing my PhD next year. Ideally, I want to take the opportunity to gather more international experience and work abroad. Nuclear fusion will be an exciting project for some time, so I could definitely see myself continuing to work in this field.
What was your motivation to write a fusion relevant Ph.D. thesis? What is fascinating about nuclear fusion?
Climate change and the ever-increasing energy consumption are problems that have been present for a very long time. Nuclear fusion aims to help solving both of these challenges and I find it inspiring to contribute to this cause. During my PhD I have also noticed a unique focus in fusion research of working towards one big common goal, which sadly seems rare today. Being part of such a collaboration is definitely a fascinating aspect and I am very happy to have worked in such a great group as I have.