Interview with Cæcilie Lundahl Andersen

Cæcilie Lundahl Andersen is a development engineer at CHEXS Aps.

Where did you graduate from and with which degree?
I graduated in March 2025 with a Master’s degree in Earth and Space Physics and Engineering from DTU (Technical University of Denmark). 

Please give a description of the work you do in your current position.
I develop optics for X-ray and neutron applications. My main project at the moment is developing a focusing neutron optics to be installed at international research facilities. As I work in a small start-up company, I handle all the technical processes related to prototype development. This includes everything from design optimization and development of fabrication processes to manufacturing and quality testing.

What motivated you to study physics or engineering in the first place?
It was never set in stone for me to become a physicist or engineer, and I didn’t really know what an engineer was until I started the journey myself. However, I have always been driven by a deep interest in understanding the universe we live in, together with a strong curiosity about the objects in the sky. I had great teachers in high school who encouraged me to nurture this interest, leading me to participate in a summer camp at the Niels Bohr Institute. While I enjoyed the academic content, I sadly didn’t feel a strong sense of belonging, which made me hesitant to pursue a degree in physics.  Instead, I applied to the Earth and Space program at DTU. I found the first semester hard, but as I found my people and built my academic confidence, the journey was fun and extremely rewarding. 

What made you decide to pursue a career in the private sector?
It has always been a priority for me to have a student job. During my studies at DTU, I worked for 3 years in a biotech company and 2 years in CHEXS as a student assistant. After graduating, I was fortunate to be given the opportunity to continue with CHEXS in a full-time role, which felt like a meaningful next step for me.  

How do you use the skills you learned as a physicist or engineer in your work?
As an engineer developing a product, I start by breaking a complex problem into smaller, well-defined problems to identify the processes that need to be developed. For each process, I determine the relevant physical parameters and use my programming skills to build simulation tools that allow me to model and optimize them. Then, I go into the lab and perform experiments to fabricate and test the components. In this way, my work is very interdisciplinary. While I am a specialist in some of the processes, others are completely new, requiring me to use the core engineering skill: the ability to acquire the knowledge necessary to solve the problems, and the determination not to give up.

Your current work grew out of your MSc research. Can you tell us about that transition from student project to startup?

I did my MSc research in collaboration with CHEXS, and as we later received funding to continue the project, it transitioned into a full-time position for me. In that sense, the transition was very easy, since I continued the work I was already doing. While my MSc research focused more on building knowledge, simulation, and initial experiments, we have now acquired facilities for fabrication and prototyping. This has led my work into a much more experimental and hands-on stage, allowing me to see my research gradually materialize into real-world applications, which is highly rewarding.

What has been the most exciting or challenging part of working in a startup compared to university life?

Working in a small startup gives me a great deal of freedom, as I plan and manage my own tasks independently. When things succeed, it is especially rewarding because I know I took every step of the process myself, which brings a strong sense of pride in the work. At the same time, this independence also means that much of the work is done alone, which can be challenging at times.  Conducting research without a university group can feel isolated, as you lack the everyday academic environment and discussion. This has encouraged me to develop stronger problem-solving skills and to be more intentional about seeking dialogue beyond my immediate working environment. 

Looking ahead, what do you hope to achieve in your role or in the company’s development?

My goal is to develop the technology needed to build a functional prototype of the instrument I am working on. My ambition is that this instrument will help reveal new insights in materials sciences where neutrons play a unique role, and to push the boundaries of what is currently possible within X-ray and neutron optics. Ultimately, I hope we can bring more people on board to share this vision. 

What does being a physicist or engineer mean to you?
To me, being a physicist or engineer means not giving up on complex problems, thinking critically, and having a genuine curiosity about how nature works, combined with a wish to contribute positively to the world. 

What advice would you give to young people (in particular women and minorities) with a background in physics or engineering who would like to pursue a career in the private sector?
Go to career fairs and speak with companies, even those you might not initially think you are qualified for.  The DSE fair was very helpful for me and an eye-opener in showing how my skills were valuable in fields beyond my specific study program. Although I did not land any of my student jobs through these fairs, it significantly strengthened my networking skills. Doing student projects with the industry ultimately led to my full-time position.

Being in a field with brilliant and ambitious people is exciting, but it can also be intimidating, especially if you feel pressure to prove yourself or become overly aware of how you are perceived as a minority. If I were to advise my younger self, I would say trust your own competence, don’t be afraid to ask the “stupid” questions, and trust your sense of justice. For me, seeking support and advice from friends has been really helpful in lifting me up and navigating difficult situations. Connecting with other women in science, such as through networks like KIF, can create a space for openness and mutual support, which I strongly encourage.