Freek Witteveen: a journey from QuSoft, and back again.
On September 1, 2025, a familiar QuSoft face came to the office in Amsterdam, this time as a senior researcher. Freek Witteveen joined CWI as a permanent researcher, affiliated with the Research Center for Quantum Software through the research collaboration. His appointment marks a new cycle for a young scientist who first joined QuSoft as a PhD student and went on to gain recognition in quantum information theory and many-body physics both in the Netherlands and abroad.
Source: QuSoft
The new role combines research, teaching, and student supervision, as well as contributing to QuSoft’s and CWI’s outreach and community-building efforts. “It’s about doing high-quality fundamental research,” Freek explains, “but also keeping the connection to society—sharing knowledge, and exploring applications in the real world.”
Freek Witteveen’s academic path has been shaped by both interdisciplinarity and course corrections. Originally from the Netherlands, he studied at the University of Amsterdam (UvA), specialising in mathematics, physics, and philosophy. His early interest in applied work led to a master’s thesis at the Centrum Wiskunde & Informatica (CWI), before embarking on a PhD in mathematical epidemiology at Utrecht University.
That endeavour proved far from Freek’s core interests. “It was a bit too applied for me,” he recalls. After a year, he left, but this decision was one of the most formative experiences in his professional journey, Freek stresses.
“I returned to UvA and CWI—this time joining QuSoft for a PhD in mathematics, supervised by Dr. Michael Walter”. This second start became a turning point: “It was the perfect environment to come back to research and develop as a researcher.”
QuSoft’s focus on quantum computing offered a middle ground between theory and potential application. Freek’s doctoral work, completed in 2022, explored quantum information and many-body physics and was awarded the Stieltjes prize for best PhD thesis in mathematics in the Netherlands in 2021/2022.
Following the PhD, he spent two years as a postdoctoral researcher at the University of Copenhagen’s Centre for the Mathematics of Quantum Theory (QMATH), before returning to QuSoft for another postdoc in late 2024.
Currently, Freek’s research spans mathematical physics and quantum information theory applied to many-body physics, with recent work focusing on quantum algorithms for chemistry. This includes collaborations that bring together quantum computing specialists, chemists, and biologists—such as the Quantum for Life project in Copenhagen.
Why QuSoft, again?
This is Freek Witteveen’s third stint at QuSoft, and the motivation to return (or to stay around, depending on one’s perspective) is both scientific and personal. He describes the centre as “one of the best research groups in Europe” for theoretical research in quantum algorithms and quantum information science, praising its open, collaborative atmosphere and breadth of expertise.
The interdisciplinary scope is a significant draw. As Freek describes it, there is computer science, mathematics, physics, and even applications to chemistry—yet “everyone works on a coherent topic”. It’s rare to have a group where collaboration is possible with almost anyone, but without everyone doing exactly the same thing.
There is also the appeal of working in the Netherlands. “I’m from here, and I’m very happy to be able to do research in the country where I also want to live.”
Looking ahead, Freek Witteveen plans to deepen the connection between quantum algorithms and chemistry, getting more domain-specific chemistry knowledge. “I think it’s one of the most important applications of quantum computing,” he says. He also aims to build links with theoretical computer scientists at QuSoft and with physicists and theoretical chemists at the University of Amsterdam, as well as maintaining collaborations abroad.
“To me, the interplay between the natural sciences and computational sciences is very fascinating, and goes in multiple directions. The core idea of quantum computing is that quantum physics enables better computation. On the other hand, quantum computation will make more precise predictions for quantum systems and give a new way of thinking about physics in terms of quantum information.”
In Freek’s view, good science requires more than just academic excellence. He also places emphasis on interpersonal relationships, especially in the context of supervision, a new responsibility he is enthusiastic about. “I think it’s important to have a culture where people are not afraid to make mistakes or not know things. It should be more like a dialogue, not the intimidating professor who knows it all on one side and the ignorant student on the other.”
Freek—who enjoys reading in his free time and tackling the cryptic crossword puzzle on Saturday with his partner—considers academia a competitive world where people work hard and things can turn out difficult. “That makes it extra important to pay attention to kindness and a certain softness,” he summarises.
This is the ‘welcoming’ environment he finds in QuSoft and CWI, which makes his return (or stay) to the centre all the more meaningful:
“I wouldn’t want to be working anywhere else.”
Photo credit: CWI/Paul Roberts