Credit: UKAEA

Ian Chapman, a nuclear physicist at the Culham Centre for Fusion Energy in Abingdon, UK, won the Cavendish Medal at the Science, Engineering and Technology Student of the Year Awards in London in March, after proving his ability to convey the significance of his research to Parliament.

Describe the work that won you the award.

To get energy from nuclear fusion, you must heat the hydrogen fuel to 150 million °C — ten times hotter than the centre of the Sun — so that the isotopes can fuse. But when you heat an ionized gas, or plasma, that much, it can become unstable. My job is to understand when and how the instabilities appear, and how to get rid of them. One example is a periodic collapse in the temperature and density of the plasma. The administrators of ITER, an international project to build an experimental fusion reactor, asked the community to investigate this instability. I chaired a collaboration of 16 labs to model the instability and demonstrate that we understand what is required to control it.

Are communication skills important for fusion researchers?

Yes. Communicating what we do is a problem for physicists in general. It's absolutely important. Awards like this help to raise public understanding of fusion, which can only be good for future funding. And, when working on large international teams, I've found that I'm good not only at generating enthusiasm, but also at helping partners to tackle problems together.

What's the status of ITER?

It is being built in the south of France, and will prove once and for all whether fusion is viable — specifically, whether we can get more power out than is put in. The first plasma in which fusion can occur should be produced in November 2019. In terms of the size and number of collaborations, ITER is similar to the Large Hadron Collider (the world's largest high-energy particle accelerator, located at the CERN particle-physics lab near Geneva, Switzerland), but some things have yet to be worked out — for example, whether researchers will remain at their home institutions or become ITER employees.

Do you have to be involved now to have a role at ITER in the future?

No. All the partners are collaborating to make ITER work so that there will continue to be opportunities for research and jobs. Those with the best ideas will get the jobs.

What challenges does ITER face?

ITER is set up so that all knowledge about how to design, assemble and run the experiment is shared among the collaborators. For example, the biggest component of ITER is the field magnets. Rather than having one partner provide those, it was decided that everyone would be involved in manufacturing them so that everyone would have the knowledge to build their own fusion power plants in future. That is a sensible long-term strategy, but it adds a lot of negotiations and complexity to the project.

What have you done to set yourself apart from other young researchers?

The vast majority of machines to heat plasma use neutral-beam injection, which spins the plasma at hundreds of kilometres per second. A mentor pointed out that nobody was looking into the effects of that on the plasma. We worked out how to model the rotational dynamics, which gave us a unique skill.

Are younger scientists flocking to fusion energy now that ITER is a reality?

Yes, the calibre of PhD students and postdocs interested in fusion has increased dramatically in the past few years. We are getting more publicity now that ITER is really going ahead, and is no longer simply a paper exercise. This is the most exciting time to work in fusion, because the next decade of work will make or break the field — and define whether fusion can work for humankind.