THE LASER USER


ISSUE 115 MARCH 2025 INTERVIEW


Q. How do you use lasers in fusion research?


As well as using lasers for diagnostics of the fusion plasma and for some remote repair scenarios, we have also specifically bought a large laser (125 kW CW infrared) for the CHIMERA project. CHIMERA will allow us to test components under the unique combined conditions of high heat flux and high magnetic fields, reproducing the harsh conditions found in magnetic confinement fusion. The laser allows us to apply heat to the surface of components, over a relatively large area, to power densities of over 100 MW per square metre.


Q. What are the biggest challenges you currently face?


One of the big challenges in fusion is the choice of materials. Inside the fusion machine will be a plasma with core temperatures in the region of 150 million o


C. Less than a few metres away, outside of the


vacuum vessel, will be materials operating at near absolute zero. The temperature gradient is enormous. As well as the ability to resist and


“


cost effective. We used to struggle to keep optics free from spatter when working at <80 mm stand-off distances. The whole industry seems far more mature, there is more awareness of the benefits and practical applications than previously. One of the encouraging developments has been in Additive Manufacturing which has gone from something of a curiosity to being a method suitable for use in aircraft (a sign of confidence in the process).


It was a pleasure to see some of the old faces at ILAS 2023, and there are lots of my former contacts who are still active in the laser industry.


Q. How are you addressing the move towards Net Zero?


We are right in the middle of the Net Zero agenda, although fusion is not the near-term solution to the world’s current problems. I believe that fusion will ultimately play a significant role in satisfying the increasing demand for low-carbon, continuous base-load energy working in conjunction with renewable energy sources.


The STEP programme will create a huge opportunity for UK organisations to get involved with fusion.


Q. How do you see the acceleration of AI impacting your sector?


”


dissipate heat, materials will also need to be resistant to damage by neutrons. In some cases, heat resistant steel alloys, for example, have been redesigned with some elements removed from the alloy and replaced with alternatives. Manufacturing techniques will also have to be developed in order to use these new materials – perhaps this represents a future opportunity for lasers.


Another challenge we face is building up supply chain readiness. UKAEA wants to stimulate the UK manufacturing and construction industry to be ready to build future fusion energy plant. For example, the STEP programme (Spherical Tokamak for Energy Production) will create a huge opportunity for UK organisations to get involved with fusion. STEP – located at West Burton on the banks of the River Trent in North Nottinghamshire, on the site of a decommissioned coal power station – will deliver net fusion power to the grid by the 2040s. UKAEA also has programmes to develop the people and skills needed to deliver future fusion projects.


Q. How has the laser industry changed since you last were involved?


One of the fundamental changes is the replacement of flash lamps for pumping lasers by laser diodes. This has resulted in higher power but also much better beam quality, which means that working distances and beam delivery can be more practical and


There is a very high level of interest in AI, and our site at Culham has been chosen as the first UK AI Growth Zone with a plan to develop a 100 to 500 MW capacity data centre. I believe that AI could be significant in helping to analyse complex physics interactions in the fusion process.


Q. What is the best thing about AILU membership for you?


For me, it was “coming back into the fold” prompted by the acquisition of our “big” laser. AILU is a great sounding board and a vital tool for networking. I have been impressed by the energy (no


“


AILU is a great sounding board and a vital tool for networking.


”


pun intended) and passion within AILU, which is infectious. Dusting off my background knowledge of laser material processing and re- engaging with the community, it has been a very useful platform to have discussions about the uses of high-power lasers and to have some highly specific questions answered by AILU members.


Contact: Chris Peters chris.peters@ukaea.uk


15


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36