Interview with Florian Schreck
Florian Schreck is a professor of Experimental Quantum Physics at the University of Amsterdam and the coordinator of Catalyst Programme 3: Quantum Sensing Applications at Quantum Delta NL. He studied physics at the University of Konstanz in Germany and received his PhD from the École normale supérieure (ENS) in Paris. After a postdoctoral research appointment at the University of Texas, he joined Rudolf Grimm’s group at the Institute for Quantum Optics and Quantum Information (IQOQI) of the Austrian Academy of Sciences. Florian then established his own research group, which he moved to the Netherlands in 2013. He currently lives in Amsterdam with his girlfriend with whom he enjoys scuba diving trips.
How did you end up in quantum physics?
I was always interested in technical things. I built stuff at home – telescopes, robots, computer control systems – and participated in German youth science competitions. When I looked at what I would like to study, I didn’t want to decide. I liked all the natural sciences. I chose physics because from there you can go to biology or computer science or maths or whatever. It’s right in the middle.
And it just so happened that quantum physics was very important in Konstanz. For my thesis, I chose the most interesting project that was available there at the time: trying to make the first Bose-Einstein condensate in Europe. We succeeded in that.
I went to Paris for my PhD, where we tried to make the first quantum degenerate Fermi gases. I had an absolutely fabulous time there. Next, I worked on ultracold quantum gases in Texas. And then I went to Innsbruck, where I later started my own research group. We succeeded in being the first to make a quantum gas of the chemical element strontium.
And that became the baseline for everything I did. We moved to Amsterdam in December 2013, won another grant, and began more and more cool experiments. We obtained funding through a European Quantum Flagship project, which I headed, then a Dutch Research Council (NWO) programme, and now Quantum Delta NL.
Could you give an example of the kind of research that you do?
We use ultracold atoms to develop extremely sensitive measurement devices for time and acceleration, which are needed for navigation for example.
Take our quantum clock research line. To build a clock, you need some kind of frequency reference. If you only knew about classical physics, you would probably use a pendulum as your frequency reference. But a pendulum is a human-made object. If you want to build a second clock, you need to build a second pendulum. You will not be able to build a second pendulum that has exactly the same properties as the first pendulum. Basically, classical clocks can’t tick the same way.
"If you know about quantum physics, you can use quantum properties to build better clocks. Atoms, after all, are constructed by nature."
As far as we know, every atom of a specific isotope is identical to every other atom of that isotope. They are nature-made standard pieces. They give you perfect frequency references. All you need to do is read them out without destroying them.
Now, the atoms can’t touch, because if they did, all the energy levels would shift around. So you need to use a gas of individual atoms. Think of the molecules in the air around you: at room temperature, they fly in all kinds of directions. That’s a problem for precision spectroscopy. But if you take a gas of atoms and cool it down to absolute zero, all the atoms will start behaving the same. You must cool them to essentially a standstill – hence, ultracold atoms. We use laser beams to slow the atoms down.
What do you do for Quantum Delta NL exactly?
I lead the ultracold quantum sensing testbed. One of our goals is to build a national quantum clock. Ultimately, we want to have a frequency reference that companies can subscribe to. This could be useful for precision timing for telecom companies, for example, or timestamping financial transactions.
Another goal is to bring ultracold quantum sensing technology closer to the market. We want to launch start-ups and help companies develop the modules or subsystems necessary for this kind of technology. We’re also trying to build a user ecosystem. At the end of these seven years of Quantum Delta NL, we want components for quantum clocks on the market. The technology looks promising. There are huge start-ups being funded in Europe and the US based on this kind of technology, with millions of euros or dollars of funding.
The toughest part of bringing this technology to the market are the laser systems. They’re horribly complicated. We will focus on making more compact and robust systems that can replace standard lab-built laser systems.
So you’re working with Quantum Delta NL to have this technology produced by companies. What’s that like? You’re a fundamental researcher, so it must be quite different for you, working with start-ups and businesses?
It was a big change for me. When I worked in Austria, we were forbidden to use research money to compete with companies. I feel like the drive to connect with companies is quite unique to the Netherlands. In the end, this is all Ministry of Economic Affairs money, so everything must have a vision towards application. It’s certainly different than thinking about fundamental research, but it’s also interesting. It’s a different type of challenge.
What I’ve noticed is that companies don’t necessarily know what’s needed. We have to first educate them and talk to their engineers. The technology of a company often doesn’t match perfectly with what we need. We have to delineate which parts the company can do, and which parts we will have to do ourselves or differently. That process is still in the early stages.
The thing is that our experiments are really complicated. It takes PhD students and postdocs a lot of time to build the required electronics or laser systems themselves. With this Quantum Delta NL research, we could outsource the construction of a laser system to one of the start-ups we are funding. And then the PhD students could focus more on the research and on assembling or designing the core of the experimental apparatus. It would all go much faster and ideally even be cheaper.
"My hope is that we will create a kind of feedback loop. By building up these start-ups and the industry, we develop tools that can feed back into our research and help us come to cool results and fundamental research. That research, in turn, will drive forward the application."
You’ve been in the Netherlands for almost ten years. How have you seen the Dutch quantum ecosystem change over those years?
It definitely grew more national, to many more cities. I think it was very Delft-centric initially. My research group moved to Amsterdam in 2013, but it didn’t particularly feel like it was part of something bigger back then. I felt a bit lonely here, doing my thing, which no one else in the Netherlands was doing.
But then all this accelerated. There was the national Quantum Software Consortium, and probably many other developments I wasn’t completely aware of, like the quantum network activities. I got invited to a brainstorm session in Delft for the National Agenda Quantum Technology. I proposed the ultracold quantum sensing testbed, and other people came in with their sensing testbeds and we joined forces.
When Ronald and Freeke and the people around them applied for this National Growth Fund proposal, it felt like becoming one family. Like coming together and trying to achieve synergy and really doing something together here. We have all these exciting projects going on.
And it’s really working. For example, a famous scientist from France has accepted a joint position with Quantum Delta NL and the universities in Amsterdam and Eindhoven to help us build up the ultracold quantum sensing testbed. It’s a lighthouse effect, you know? Together, bundled up, you can see that it really is something, also from other countries.