Can we use quantum computers in a way that is also relevant to society? With the help of a 2-million-euro NWA grant, Leiden University will work with partners such as Surf, Google and Volkswagen to demonstrate that quantum computers are also of value outside the lab.
In 2019, Google came out with the news that they had succeeded in demonstrating ‘quantum supremacy’. In other words, irrefutable proof that quantum computers can solve certain problems much faster than conventional computers. ‘We already knew this in theory,’ says Dr Alfons Laarman, researcher at LIACS and leader of the consortium, ‘but to extract solutions from a quantum computer in practice is quite the challenge. As soon as you try to read out your data, you lose the advantage a quantum computer provides. That is simply how quantum mechanics work.’
Reading out a quantum computer
Quantum computers are in some cases much faster than normal computers. But extracting the answer to a calculation from a quantum computer is not easy: quantum mechanics work in such a way that you can unintentionally change the answer just by looking at it. Doing precise calculations under such circumstances is a huge challenge.
A very specific programme
But quantum supremacy alone is not enough: ‘To demonstrate quantum supremacy, Google used a very specific programme that is actually of no use at all. The only thing the programme had to do was to be faster on a quantum computer’, says Laarman. To demonstrate that these computers can also mean something to society, we need to take the step towards ‘quantum advantage’, proof that you can solve real-life problems much faster with a quantum computer as well. However, existing quantum computers are still too small for this.
Approaches from two sides
With the money that Laarman’s consortium has received from the NWA they want to take important steps towards quantum advantage. ‘To do this we are approaching the task from two sides: on the one hand we want to chop up existing problems of companies into bite-sized pieces so that they are suitable for current quantum computers. On the other hand, we are working with researchers and technology partners such as QuTech and TNO to prepare quantum computers themselves for these problems.’
Truly a different field
In the very best case, the consortium will be able to bring supply and demand together in such a way that they can achieve quantum advantage. Laarman: ‘If not, we will still have developed a great deal of new expertise and manpower that can work with quantum computers in the future. At the end of the day, quantum computing is a totally different field than regular computer science. Experts have to start over from scratch. So it’s good that people are gaining experience already.’
Talking to society
Apart from the goal of demonstrating the societal importance of quantum computers, there is also a major outreach component to the NWA grant. ‘We want to engage with society in order to increase public awareness of quantum computers. For example, we can now continue with ‘Quantum Rules!’ at the faculty, with which we teach secondary school students about quantum technology. We are also going to conduct research into the perception of quantum in society’. After all, quantum computers may be ready for society, but is society ready for quantum computers as well?