Interview with Spinoza Prize winner Lieven Vandersypen

Lieven Vandersypen, Professor in Quantum Nanoscience and scientific director of Qu-Tech, has been awarded a Spinoza Prize for his pioneering work on quantum computation, which holds great promise for global problems in health, climate and energy. With his prize Vandersypen also intends to encourage girls to go into the field of technical sciences, as well as help people tell the difference between facts and fabrications. “The first time I heard about quantum computers I thought: how are these things possible?"

Q: What is your reaction to receiving this prize?

“I’m very honoured. It’s the highest scientific recognition you can get in the Netherlands, to receive it is really fantastic. Of course it’s a personal prize but all the work we do is really team work. So I also want to express my thanks to the many collaborators over the years within our Kavli institute and from abroad, especially my mentors Hans Mooij and Leo Kouwenhoven. I see this prize as a carte blanche from the Dutch Research Council: they have the confidence that you will do good things with the prize money. That flexibility is unusual, which makes it extra valuable.”

“The nature of the Spinoza prize is quite similar actually to what Fred Kavli had in mind with the Kavli Foundation: through this organization he selected a number of institutions, endowed them with significant sums of money, trusting that they would do good things with them to advance nanoscience, neuroscience, astrophysics and so forth. The foundation looks carefully who has done excellent work and deserves to get this flexible money, who knows how to best to use it to advance the science in their institute. With the Spinoza prize and also with Kavli funds we as scientists have the freedom to say: we are going to do this because we believe it’s worthwhile.

Q: What is the promise of quantum computing?

"One reason why you don’t see many concrete promises, is because I don’t want to add to the height of the inflated expectations in this field. On the other hand: quantum computers can have a strong impact. These computers work on different principles than computers we work with today, offering much faster solutions – meaning the difference between millions of years in a practical time scale and an hour, or minutes. We know that quantum computers can offer a speed up for
important classes of problems, and not in others.”

“In the first category where it is possible to get a quantum speed-up, the most firmly established methods are able to compute efficiently the properties of molecules and materials. This can have societal implications. Because if you can efficiently compute the properties of molecules and materials – todays super computers cannot, it’s too hard for them – it can speed up the design of new drugs, new catalysts that make chemical plants efficient for example, lead to better fertilizers or batteries... This can ultimately can contribute to health, climate, the energy transition etc.”

“The reason why it’s difficult to compute the properties of molecules and certain materials, is because these properties are directly influenced by interacting quantum systems, interacting electrons. When that happens the complexity of behaviour grows exponentially with the size of the system. However, the quantum computer already has that same exponential complexity build into it, so it’s uniquely fitted to the properties of molecules and materials.”

Q: Can you describe the focus of your work?

"My expertise is in building quantum computers and quantum bits that we can program, control and take through the steps of algorithms; what we call quantum hardware. Our mindset is: the more, the better, the easier. As we increase the number of qubits and the degree of control, in addition we should make things easier over time. For instance, going from 10 to 11 qubits should be easier than going from 2 to 3 – if not, we are on a bad trajectory. Quantum simulation is a parallel line of our research: building a system that very much resembles a different system which we would like to understand better.”

Q: Do you have a specific mission in mind with this prize?

"I will apply the Spinoza award to support these two research lines in the coming years. In addition to this, I also want to find ways to support two causes that are closely connected to what we do here and which I care about a lot. The first is to encourage girls at the high school level to go into the field of physics or other technical sciences. I think girls are underrepresented and it’s not because they are uninterested: its often because they think incorrectly that physics just for boys or that they are not smart enough. This is a missed opportunity for the progress of science and the people involved.”

“The second cause I want to support I consider the most important thing for our society these days: to help people tell the difference between scientifically proven or investigated facts and simple fabrications that somebody came up with. Many find this distinction difficult, which is a problem for our society. For example, I understand people being afraid of getting a corona vaccine; what I have difficulty with, is the people who are merely spreading lies and fabrications. Even for smart people it’s difficult to understand why they should believe an expert in virology more than a random dance teacher. I want to use this prize to disseminate science in non-scientific venues - ‘Spinoza te Paard’ by Leo Kouwenhoven is a great example of this.”

Q: Which aspect fascinates you most about your work?

“The fact that some of the deepest aspect of quantum physics, which are very counter intuitive but also fascinating, can be applied to build a computer that works in a completely different way than computers that currently exist, and which is also extremely powerful. That’s such a fantastic combination, right? The most fascinating deep properties of nature coming together with a potential for technology that can be really impactful. This combination inspires me a lot. The first time I heard about quantum computers, I almost couldn’t sleep from excitement: how are these things possible?”

“Still, if you think about what we are doing it continues to be remarkable. In our case we can hold onto one electron – almost unimaginable! – and we can actually read out the spin of the electron: that one is spin up, that one is spin down. All at the level of individual electrons. And we can actually control their states, and couple them together, and make them go through the steps of a computation. That fascination, which I’ve had for almost 25 years now, hasn’t diminished. It keeps me motivated and working in this field.”

Q: In the future, do you imagine we will be seeing more of quantum computers in daily life?

“That’s hard to say. I think the mental picture I have today of a future quantum computer is a very expensive machine in a large, specialized facility, that will be used by companies, institutions or government agencies to solve important problems that they cannot solve even with super computers. So my mental picture of a quantum computer is more similar to what a super computer looks like today, rather than what a laptop or a cellphone looks like today, which are available almost in any household these days.”

“Of course it’s hard to predict the future of quantum computing. Certainly when the first computers were built decades ago, I think nobody imagined that a machine orders of magnitude more powerful than they were building then, now fits in our pockets. When you ask me today ‘would a laymen person need a quantum computer?’ I would say no, a normal laptop is fine. But I have to admit, when Steve Jobs gave his famous speech 15 years ago “And here it is, the iPhone” my first thought was: that’s stupid I don’t need that, why would anybody care?”

Q: Do you foresee ethical or philosophical implications of quantum computing in the future?

"We have a vision team at TU Delft on quantum computing which is now composing its conclusion: we reflect on the possible applications of this new technology together with all kinds of people, from industry, and governments to advocacy groups and privacy experts. Once you are conscious of ethical implications, there are ways to build this into the technology: so that positive outcomes are landing more easily than negative outcomes. As a scientist we cannot say; ‘We do the science and develop the technology, let somebody else think about implications.’ We can’t stay on the sidelines. I don’t pretend that I will have complete control over it, but it starts at least with caring and participating.”