From mathematics and cryptography to organisational risk and Belgium’s academic expertise, Sarah’s story shows how much of quantum preparation begins long before a powerful quantum computer arrives. It starts with understanding what organisations depend on today and bringing together the expertise needed to prepare those systems for tomorrow.
Where did your fascination with cryptography begin?
It started during my degree in mathematics. I came across cryptography as an application of mathematics and immediately found it fascinating. I wanted to understand more about how it worked and how I could apply that knowledge professionally.
That eventually led me into consulting, where cryptography became part of my work.
When did quantum become tangible for you?
Quantum entered the picture through cryptography.
During my thesis at KU Leuven, I learned more about the fact that many cryptographic algorithms used today could become vulnerable once sufficiently powerful quantum computers become available.
I was fortunate to be studying in an environment where researchers were working on alternatives for a post-quantum future. One of the teams in Leuven had contributed a candidate to the international standardisation process for post-quantum cryptography.
That made me want to understand the technology behind it. I had never been particularly enthusiastic about physics before, but suddenly I wanted to know how quantum physics worked. I eventually took a course after finishing my thesis, and from there my interest kept growing.
What does quantum mean for your work at EY today?
Most of my work focuses on the cryptographic risk linked to quantum computing.
Organisations want to understand what they need to prepare, which systems could be affected and how they can approach a migration towards cryptography designed to remain secure in a quantum era.
There are opportunities on the computing side as well, for example in optimisation. For many organisations, however, the required investment can still be substantial compared with the certainty of the outcome.
Today, much of our work is therefore focused on identifying where quantum computing could affect cryptography within an organisation and determining how those risks should be addressed.
We also spend time keeping up with developments in the field. The Quantum Circle newsletter is one of the ways we do that.
Why should organisations start preparing now?
Cryptography is often described as the backbone of security.
The difficulty is that this backbone tends to remain hidden. When everything works, people are understandably reluctant to touch it because changing cryptographic systems can introduce problems.
But postponing every change creates another risk.
You can make changes while you still have time to test and fix things, or you can wait until those changes become unavoidable.
At the same time, this needs to be treated as a risk exercise. Some data may have limited sensitivity or a short lifespan. In those cases, an organisation may decide that waiting is acceptable.
Other information may remain confidential for many years. For those systems and data sets, the risk can be much more significant and migration will become necessary.
Is that also where Quantum Circle becomes valuable?
Yes. Before joining Quantum Circle, I was working on many of these topics rather independently within my immediate team.
I wanted to meet other people who were interested in quantum technology and who were working on similar subjects. I wanted to hear what they were seeing, how they approached the future and what we could learn from each other.
That exchange of expertise has been one of the most valuable parts for me.
What made you want to join Quantum Circle?
The community offered an opportunity to connect with people working on similar challenges and to create things together.
One example is the first Quantum Circle white paper. I really enjoyed bringing expertise from several members together into something that could help a wider audience.
There is still a lot of awareness work to do. Many people know very little about quantum technology or what it could mean for their organisation. People working in this field can help by sharing what they know in an accessible way.
If people are interested, great. If they are not yet interested, we may simply need another way to reach them.
How has Quantum Circle developed since you joined?
The community has become more diverse. More organisations are interested, and people with different backgrounds are getting involved.
Some recurring challenges remain, especially around reaching people outside the group that is familiar with quantum technology.
We have also learned which formats work best. The newsletter, for example, has become an established part of the community. That was not there at the beginning.
I think the community has matured over time, both in terms of its members and the ways we share knowledge.
Can you give a concrete example of what the network has led to?
The network itself has been very valuable.
At EY, for example, there is a global alliance with IBM. But a global alliance becomes much more useful when you know the people involved locally.
Through the Quantum Circle network, I met someone from IBM. We started talking about how that existing relationship between EY and IBM could become more useful locally as well.
We have not necessarily completed a joint project as a direct result, but we know each other now. If an opportunity comes up where one organisation can help the other, that connection exists.
Quantum Circle has also given me opportunities to present at events that I might not have had otherwise. And contributing to a white paper together with recognised experts adds credibility to the work.
A global network is useful. Knowing who you can actually contact makes it much more valuable.
Is it difficult to share knowledge between organisations?
I do not really experience it that way.
A lot of technical information is publicly available. The value we can add often comes from making that information easier to understand and bringing it to people who would not necessarily search for it themselves.
Most people can find information about quantum computing online. Far fewer will spend their time looking through academic research on post-quantum cryptography.
That is where a community can contribute. We can bring the subject into settings where people might otherwise never consider it.
How do you see Belgium’s position compared with neighbouring countries?
There are two sides to it.
When you look at national strategy and investment, Belgium has less activity than countries such as the Netherlands and Denmark. The United States operates at another level again in terms of available resources.
At the same time, Belgium has considerable expertise in algorithm development.
That includes post-quantum cryptography. Researchers from Leuven, for example, contributed to candidate algorithms in the international post-quantum cryptography standardisation process.
So the knowledge is here.
The opportunity for Belgium is to make greater use of that expertise outside academia and bring more of it into industry.
Where can Belgium make better use of its academic expertise?
Academic research is often written for other academics.
Companies need that research translated into something that relates to their own organisation, their use cases and the issues they face.
There is also an enormous amount of information available. Expecting business leaders to find the relevant research themselves, understand it and translate it into their own context is unrealistic.
Someone has to make that translation.
And that requires an unusual combination of expertise. You need enough technical knowledge to understand the research, but you also need enough business knowledge to understand the organisation and its needs.
Having both in one person is uncommon.
What role can public authorities play?
Authorities can have considerable influence.
We have seen that in banking. The possible impact of quantum computing on cryptography had been talked about for several years. When the National Bank of Belgium began asking banks about the subject, action followed.
If public authorities want more progress, they can make resources available, support initiatives that exist today or introduce requirements organisations need to address.
Personally, I would prefer support and investment where possible.
I would also favour strengthening existing expertise rather than creating an entirely new quantum hub and starting again from zero.
For example, funding people who can translate academic quantum research into business applications could address a concrete need while making use of expertise Belgium has today.
What would you like Quantum Circle to focus on next?
One area I would like to see developed further is bringing academic developments closer to industry.
Belgium has strong research, and helping organisations understand how that research relates to them could create a lot of value.
A second ambition would be to demonstrate specific quantum applications through a proof of concept or a demo. Something people can experience instead of only reading about.
And the community itself remains essential. We have tried different ways of involving more people, with varying results. Finding ways to bring more professionals working with quantum technology into the community remains important.
What would you tell organisations that have not started exploring quantum technology yet?
Engage with people working on it.
Quantum computing can sound extremely complex from a distance. But spend an hour with someone who works in the field and much of that complexity becomes easier to understand.
Explain your doubts as well. Tell us what is stopping you.
That helps us understand the barriers organisations face and gives us an opportunity to see whether those concerns can be addressed.
Some companies may be working on quantum initiatives without speaking publicly about them. Others may not be doing anything because they have assumptions about the technology that change once they learn more.
So engage. Talk to us.
Where would you like Quantum Circle to be in five years?
I would like Quantum Circle to become a trusted reference for quantum technology.
When something comes from the community, people should associate it with reliable expertise. And when organisations have a question about quantum, visiting the Quantum Circle website should become a natural first step.
The easiest comparison is probably Spotify.
This interview is part of Inside the Circle, our series featuring the people advancing quantum innovation in Belgium. Discover the full series here.
