ºÚÁÏÍø

News

Doctoral thesis on nuclear fusion at over one hundred million degrees Celsius awarded European physics prize

Henri Kumpulainen's PhD thesis found out how to best predict the behaviour of fusion energy materials in temperatures of over one hundred million degrees Celsius.
A man in a dark suit and white bow tie against an orange dotted circle and dark background.
Henri Kumpulainen. Photo: Jarmo Vääriskoski, illustration: Ville Heirola/Aalto University.

Current nuclear energy production is based on fission, which also produces dangerous and long-lasting nuclear waste. Its flipside is nuclear fusion, which generates the same amount of energy with considerably less waste. That is why researchers have for decades now been attempting to build a fusion reactor—a device that turns hydrogen into plasma to create energy. One example is the international megaproject ITER in France, set to produce nuclear fusion energy sometime in the late 2030s.

The biggest technical problem is the plasma itself: its temperature is well over 100 000 000 degrees Celsius and nothing survives contact with it. The donut-shaped reactor uses magnets to keep the plasma intact in a vacuum. Then the problem becomes how to extract the energy generated by the plasma without destroying the vacuum chamber. 

‘One solution is to build the chamber out of tungsten. It can withstand high temperatures and the erosion caused by the plasma. But even a tiny number of tungsten impurities can weaken the relationship between the energy used to heat up the plasma and the overall energy created by the reactor. Right now, researchers are focusing on predicting tungsten’s behaviour in the plasma,’ says Doctoral Researcher Henri Kumpulainen

Graphic illustration of nuclear fusion with two orange circles, abstract shapes, and text 'Nuclear Fusion'.
Nuclear fusion sees atomic nuclei collide at high temperatures and pressure to create energy. The same process takes place inside the Sun. Illustration: Margot Lepetit/Aalto University.

Kumpulainen’s thesis recently won the European Physical Society’s 2025 Plasma Physics Division PhD Research Award. The thesis was completed at Aalto University in 2023 and directed by Department of Applied Physics Professor Mathias Groth.

’My PhD research showed that new simulations can predict the behaviour and qualities of tungsten much more accurately than previous ones. That helps reduce impurities in the plasma, which, in turn, in a step towards a functional fusion reactor.’

Kumpulainen headed to Germany after graduating with his PhD.

 â€˜I received a two-year grant from the Finnish Cultural Foundation for carrying out research in Germany at Forschungszentrum Jülich, where I had already visited multiple times. So I moved to Jülich and started as a postdoc in February 2024. Now I work on simulating deuterium-based plasma—wall interactions in fusion devices.’

For Kumpulainen, the main thing is to help develop technology that could some day revolutionise global energy production.

‘After February next year, my plan is to keep working on fusion and plasma physics either in Finland, Germany or elsewhere, depending on how jobs and grants are available,’ Kumpulainen says. 

  • Updated:
  • Published:
Share
URL copied!

Read more news

Visit to an informal neighborhood, presenting inconsistent building practices in Rufisque, Senegal.
Photo by Daniel Gog-Ciceu
Cooperation, Studies Published:

TUM + Aalto SGT summer course explores economic land dynamics in West-Africa through innovative simulation

The summer course offered a dynamic simulation on land economics tailored for West African countries: Liberia, Ivory Coast, Ghana, Togo, and Benin.
Interview of a woman moving from an informal settlement to new social housing developed by NGO UrbaSEN in Dakar, Senegal.
Photo by Sofia Pascolo, Aalto SGT Student
Cooperation, Studies Published:

SGT Studio'25: Students explore sustainable and affordable housing solutions in Senegal

For the first time, Aalto’s Sustainable Global Technology (SGT) Studio course has initiated a project in Senegal, focusing on affordable and sustainable housing.
Artistic illustration: Algorithms over a computer chip
Research & Art Published:

Aalto computer scientists in STOC 2025

Two papers from Aalto Department of Computer Science were accepted to the Symposium on Theory of Computing (STOC).
Sähkötekniikan korkeakoulun vuoden alumni 2023 Heikki Holmberg kuvattuna Otaniemessä Micronovan tiloissa Okmeticin piikiekko-laatikko käsissään. Holmberg pääsi seuraamaan jo opiskeluaikoina puolijohdealalle merkittävän Micronovan rakentamista. Kuva: Niina Norjamäki / Aalto-yliopisto
Awards and Recognition Published: