Berkeley Lab's New Fusion Materials Breakthrough, Explained

 SCI-FI-TEK 70YRS IN THE MAKING

By Haley Zaremba - Aug 08, 2026

• Scientists at UC Davis and Berkeley Lab found that titanium-palladium foils trigger deuterium-deuterium fusion reactions more frequently at lower temperatures, chipping away at one of fusion's biggest cost barriers.
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• The findings, published this month in Nature Communications, open up a research path called materials-driven fusion, where reactor materials actively boost reactions instead of just surviving them.
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• The discovery could feed directly into DuctGPT, an AI tool being built at Ames National Laboratory to identify fusion-ready materials, tying the breakthrough to the industry's push to solve AI's own energy problem.

Scientists at UC Davis and Lawrence Berkeley National Laboratory just made a major breakthrough in the design of nuclear fusion reactors. The team is at the vanguard of a new field of nuclear fusion research known as materials-driven fusion, which focuses on what the reactors are made up of in order to maximize efficiency and lower the temperature at which fusion can reliably occur.

“Instead of designing materials just to survive the harsh conditions of fusion, researchers might be able to design materials that boost the reaction in specific conditions, similar to the way catalysts speed up chemical processes,” states a recent press release from the Berkeley Lab.

In a paper written about the breakthrough, published this month in the scientific journal Nature Communications, the team describes how metallic foils made of titanium and palladium can facilitate deuterium–deuterium nuclear fusion reactions at far greater frequencies at lower temperatures than is typically possible. This represents a major breakthrough, as the ultra-high heats used in fusion experiments require huge amounts of energy inputs that render most fusion reactions net-negative in terms of energy production. Furthermore, these high heats are incredibly hard on the materials involved. Together, these hurdles represent some of the greatest challenges to making fusion commercially viable.

While the discovery described in the Nature Communications paper is important in and of itself, the further research that it will catalyze in the field of materials-driven fusion is even more important. “It gives you a new knob to turn that you didn’t have before,” Arun Persaud, head of the Fusion Science & Ion Beam Technology group in Berkeley Lab’s Accelerator Technology & Applied Physics (ATAP) Division, was quoted in the press release. “If we understand this effect better, it opens the door to engineering new materials that would affect the fusion rate under certain conditions. Someday future progress might enable more compact and efficient neutron generators, which have all kinds of applications, like cargo screening, planetary science, and medical therapy and imaging.”

Materials-driven research has become increasingly common and increasingly promising thanks to the integration of artificial intelligence within the fusion sector. Large language models are being used to rapidly model different materials to find the best fit in a process that would otherwise be like looking for a needle in a haystack.

Scientists at the Ames National Laboratory in Ames, Iowa are currently building an artificial intelligence tool designed for just this purpose, called DuctGPT. The tool uses large language modelling in combination with physics modeling to find materials suitable for the harsh environment of a nuclear fusion reactor. The breakthrough at the Berkeley Lab could directly tie into the work at Ames, as any new data and model fed into the machine, such as their newest findings, can help refine the system and make research more efficient and effective moving forward.

In this way, artificial intelligence could hold the key to solving the selfsame energy crisis that it is creating. While there is huge uncertainty surrounding exactly how much energy AI will gobble up in the coming years, we do know that it’s enough to pose a real threat to global energy security. Finding a way to power the AI boom without compromising on climate goals and other competing energy needs will require major technological advances, both in the way we produce energy and in the way that AI uses it.

“There’s no way to get there without a breakthrough,” Sam Altman, CEO of ChatGPT creator OpenAI, said at the World Economic Forum’s annual meeting in Davos in 2024. “It motivates us to go invest more in fusion,” he went on to say. And now, increasingly, that investment is now using AI tools to solve AI’s problems. Tools like DuctGPT could very well be our best bet for innovating our way out of crisis.

By Haley Zaremba for Oilprice.com 

 SCI-FI-TEK 70YRS IN THE MAKING

Commonwealth Fusion Systems raises a further USD1 billion

Monday, 3 August 2026

World Nuclear News

US private fusion company Commonwealth Fusion Systems announced it raised USD1 billion of additional equity financing - the single largest funding round among fusion energy companies worldwide since CFS announced its USD1.8 billion Series B round in 2021.
 

(Image: CFS)

"With this capital, and the USD863 million the company raised last year, CFS has now raised a total of USD4 billion," the company said. "This USD4 billion represents about 30% of the total capital raised by the fusion industry to-date, reinforcing CFS's position as the world's largest and leading fusion company."

CFS said its global network of private investors expanded with the addition of a growing number of institutional investors, including pension funds, sovereign wealth funds, infrastructure investors, and industrial corporate partners. "This widening diversity and maturation of CFS's capital stack reflects the real evidence investors see in the assembly of SPARC and parallel development of its ARC power plant," it said. "In this concrete progress, investors see that CFS is maturing and have expressed trust in CFS's focused approach to commercialising fusion."

CFS said it will use the funds raised to further accelerate its progress to commercialisation.

CFS - spun out of the Massachusetts Institute of Technology in 2018 - is currently building the SPARC prototype fusion machine at its headquarters in Massachusetts. It is described as a compact, high-field, net fusion energy device that would be the size of existing mid-sized fusion devices, but with a much stronger magnetic field. The donut-shaped device will use powerful electromagnets to produce the right conditions for fusion energy, including an interior temperature surpassing 100 million degrees Celsius. It is predicted to produce 50-100 MW of fusion power, achieving fusion gain greater than 10. 

The plan is for SPARC to pave the way for a first commercially viable fusion power plant called ARC, which is intended to generate about 400 MWe - enough to power large industrial sites, or about 150,000 homes. ARC, at the company's Fall Line Fusion Power Station in Chesterfield County, Virginia, is scheduled to deliver power to the grid in the early 2030s.

"CFS is making what once was impossible into inevitable," said the company CEO and co-founder, Bob Mumgaard. "In the 2030s, we will put commercial fusion on the grid. We have the science that works and the proven execution that's consistently validated by the market. We regularly welcome investors from around the world to our headquarters in Devens, Massachusetts, where they see real and tangible progress as we ready support systems and finalise the assembly of SPARC. In unlocking commercial fusion energy, we're on a path to make an impact at a civilisational level."

KIT becomes research hub for fusion technology

Federal government relies on KIT's expertise in building a fusion reactor

Karlsruher Institut für Technologie (KIT)

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Cross-section of a future fusion power plant with plasma at a temperature exceeding 100 million degrees Celsius. (Illustration: ITER)

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The Fusion Action Plan initiative was launched by the Federal Government to advance the construction of the Germany’s first fusion reactor. This involves establishing three research hubs. The aim is to pool expertise from science and industry to master the technological challenges associated with fusion energy. A request for proposals for three hubs to receive funding had been launched by the Federal Ministry of Research, Technology and Space (BMFTR). On July 29, 2026, the BMFTR announced its decision: One of the hubs will be set up at KIT. KIT’s research will focus on the development of the fuel cycle and new materials, and the technical implementation in the fusion power plant.
 

Petra Olschowski, Baden-Württemberg’s Minister for Science, Research, and the Arts, emphasized that the decision by the BMFTR will strengthen German fusion research and Baden-Württemberg as a center of science and innovation. “How soon fusion can play a role in the energy mix of the future depends mainly on the technological progress made in materials research and in the development of the fuel cycle. This is exactly where the Karlsruhe researchers rank among the world’s best: Materials suitable for fusion reactors are a decisive building block when it comes to enabling fusion technology. An equally relevant asset are the key skills KIT can provide for setting up a safe and sustainably working fuel cycle including the production of tritium, the element necessary for a working fusion process. The fact that KIT has been chosen for setting up one of the hubs will strengthen the leading role of Baden-Württemberg in fusion research in the long run. It clearly demonstrates the success of our approach, which focuses on future technologies and the alignment with the High-Tech Agenda Germany.” 
 

Karlsruhe as an Ideal Site

“I’m very happy about the decision made by the Federal Ministry,” said Professor Jan S. Hesthaven, President of KIT. “We’re among the top institutions for fusion technology. Our expertise and our unique infrastructures make KIT an ideal site for this research. The Karlsruhe fusion hub will allow us to advance our research specifically in view of the key requirements for future fusion power plants.”
 

“Fusion energy has the potential to provide enormous amounts of energy. We at KIT are working to make it usable in practice as soon as possible,” said Professor Christoph Kirchlechner, speaker of the Fusion Program at KIT. “Together with our partners, we are developing technologies to enable safe, reliable, and economically viable fusion power plants.”
 

Industry will play a key role in this effort. According to Kirchlechner, the aim of the hub is to involve companies in the development of the technologies and to jointly establish the foundations for an efficient supply chain in the fusion industry. As the interface between the different fusion industry branches, the Karlsruhe hub brings together the Proxima Fusion and Gauss Fusion magnetic fusion companies with the Focused Energy and Marvel Fusion laser fusion companies. In total, more than 30 partners are involved in the effort. This includes universities, non-university research institutions, and established industrial companies. 
 

Three Hubs Pave the Way to the Fusion Reactor

While two hubs will focus on magnetic confinement fusion and laser fusion, the third one is dedicated to the fuel cycle, the development of new materials, and the technical implementation in the power plant. KIT had applied for this hub to contribute the institution’s long-standing know-how and speed up the transfer of scientific findings to industrial applications.
 

KIT is renowned as one of the internationally leading institutions in these areas. The research conducted by the KIT researchers includes the development of breeder blankets, which are required for synthesizing tritium as the fuel for fusion reactions, technologies for its safe fuel-cycle management, and materials that permanently resist the extreme temperatures and high neutron fluxes. 
 

In addition, key technologies such as high-frequency systems for plasma heating and components for the continuous operation of future plants are being developed at KIT. “It’s crucial to devise and combine these technologies with integration in mind,” said Kirchlechner. “This is the only way to arrive at solutions that work reliably in the power plant and can be operated economically.”
 

From Large-scale Research to Industrial Application

Considerable scientific and technical challenges must be overcome until a fusion power plant can actually supply power to the grid. At the same time, nuclear fusion is gaining momentum worldwide as a strategic future technology. Thus, fundamental research, the development of technologies, and educational efforts are closely linked at KIT. This includes areas such as providing highly specialized test facilities and qualifying specialists for handling complex systems such as the fusion fuel tritium. The aim is to establish the preconditions for developing fusion technology as a reliable complement to renewables in the long term. 

 

More information

More about the KIT Energy Center
 

In close partnership with society, KIT develops solutions for urgent challenges – from climate change, energy transition and sustainable use of natural resources to artificial intelligence, sovereignty and an aging population. As The University in the Helmholtz Association, KIT unites scientific excellence from insight to application-driven research under one roof – and is thus in a unique position to drive this transformation. As a University of Excellence, KIT offers its more than 10,000 employees and 22,800 students outstanding opportunities to shape a sustainable and resilient future. KIT – Science for Impact.

 SCI-FI-TEK 75YRS IN THE MAKING

Fusion supply chain spend up, but challenges remain

Tuesday, 23 June 2026

The Fusion Industry Association has reported that supply chain spending by the fusion industry rose 25% to USD538 million in 2025, but ensuring access to specialist materials and fuel systems remains a continuing concern.
 

(Image: FIA report)

The figure, in the The Fusion Industry Supply Chain 2026 report, is based on interviews with 25 fusion companies and 67 fusion suppliers. It suggests that progress is being made to overcome the "chicken-and-egg" problem of fusion companies needing to ensure future supply chain capacity, but also having to ensure that suppliers have confidence in their plans to make investments.

According to the report, more than two-thirds of fusion companies have seen established suppliers "pivoting to fusion". It reports that 75% of suppliers had made investments to expand their fusion capacity during 2025 but says "there is still work to do, as 69% continue to report a lack of long-term visibility of fusion needs, making planning and investment difficult".

The main supply chain bottlenecks identified are power systems and power components (48%), heat management technologies (44%), and vacuum vessels and pumps (both 32%). Meanwhile 48% of fusion companies named fusion fuel cycle systems as a major future concern. Forty per cent of the companies also have future concerns about the need for commercial-scale access to materials which can withstand extreme conditions.

Andrew Holland, CEO of the Fusion Industry Association (FIA), said: "Our fourth annual report sees considerable progress in the relationship between fusion developers and their supply chain. We see signs of the chicken-and-egg gridlock raised in previous reports easing, as supplier relationships improve and new and existing suppliers invest in scaling up capacity to meet the sector's growing needs.

"In large part, the winner of this race to fusion will not be the country that gets there first, but the one with the strongest, most integrated supply chain. Building that capability and capacity will need a truly collaborative effort between policymakers, investors, the supply chain and fusion companies."

The recommendations set out in the report by the FIA include: Governments and investors should nurture specialist fusion suppliers with a focus on key bottleneck areas such as precision engineering, high-spec materials and components, and fuel-cycle technologies; Strengthen supplier-developer communication through regular industry forums, events, and matchmaking initiatives; De-risk supplier investment through demand visibility with fusion developers providing “clearer demand signals through long-term agreements, forward purchasing, and early supplier engagement; Accelerate standardisation and pre-competitive collaboration with shared standards, specifications, and testing protocols; Expand access to shared infrastructure and test facilities such as national labs; Close the supply chain funding gap which causes a “mismatch between funding for fusion developers and their suppliers”; Streamline regulation and enable global supply chains - governments worldwide should pursue harmonised regulatory frameworks, targeted tariff exemptions, and support for cross-border collaboration; Accelerate the development of fusion fuel systems supply chains infrastructure.

The Fusion Industry Association is a US-headquartered international non-profit independent trade association for the private nuclear fusion industry. It was founded in 2018. The report was launched at The Fusion Supply Chain Trade Show in New Mexico in the USA.

SCI-FI-TEK 70 YRS IN THE MAKING

Tennessee becomes first US state to set up fusion regulations

Friday, 12 June 2026

Tennessee has become the first US state with its own regulatory framework for nuclear fusion machines.

(Image: Type One Energy)

In 2023, the US Nuclear Regulatory Commission (NRC) announced that it would base its regulatory framework for fusion energy systems on its existing process for licensing the use of byproduct materials: such systems would generate electricity from the energy released when hydrogen atoms are combined to form helium, rather than the splitting, or fission, of uranium atoms. This means that such systems fall outside the requirements to be regulated by NRC as nuclear reactors, as they do not involve special nuclear material (plutonium, uranium-233 or enriched uranium) and cannot produce the self-sustained neutron chain reaction that defines nuclear fission reactors under NRC regulations.

In response to this, Tennessee - which is an Agreement State, meaning it is authorised to license and inspect byproduct, source, or special nuclear materials used or possessed within its borders under a special agreement with the NRC - filed an amendment to its regulations setting out the framework for how it will register and license fusion machines, processes, and related activities.

Chapter 0400-20-14 of the Effective Rules and Regulations of the State of Tennessee, as well as its associated definitions, establishes requirements for the licensing of fusion machines and fusion-related activities in the state. The new regulations came into effect on 9 June.

"Tennessee has been named the top state in the nation for nuclear energy industry growth, and for good reason," said Tennessee Department of Environment and Conservation (TDEC) Commissioner David Salyers. "This latest step supercharges our reputation as the global hub for nuclear innovation and positions us as the most responsive state to new advanced nuclear companies clamouring to call Tennessee home."

In January, US fusion energy developer Type One Energy submitted an initial licensing application in preparation for the construction of a fusion power plant at Tennessee Valley Authority's (TVA) former Bull Run fossil plant site in Clinton, Tennessee. The company's commercial site near Oak Ridge is anticipated to be among the first licensees under this new framework and will function as a fusion development campus through projects between the Oak Ridge National Laboratory, TVA and the University of Tennessee, TDEC said. Construction of Type One's Infinity Two - a 400 MWe baseload power plant using stellarator fusion technology - could begin in 2028 under the new regulatory rules.

SCI-FI-TEK 70 YRS IN THE MAKING

DOE approval of Xcimer fusion power plant preconceptual design

World Nuclear News

Wednesday, 10 June 2026

The US Department of Energy has formally approved Xcimer Energy's preconceptual design and technology development roadmap milestone for Athena, the company's architecture for fusion power plants.
 

Athena (Image: Kilograph / Xcimer)

Athena is the reference architecture for Xcimer's planned fleet of fusion power plants. Designed for continuous operation, industrial scale, and a fuel cycle that renews itself, Athena integrates the company's proprietary excimer laser platform with target delivery, fusion chamber, tritium breeding, and power generation systems engineered from the outset for industrial scale.

Denver-based Xcimer's 724-page submission provided Department of Energy (DOE) reviewers with a detailed assessment of plant performance targets, economics, system-level engineering requirements, safety and environmental analyses, and technology development pathways required to achieve commercial fusion power.

"The question facing laser fusion is no longer whether the physics works," said Conner Galloway, CEO, Chief Science Officer, and co-founder of Xcimer Energy. "The question is how fast we can industrialise it. DOE's acceptance of Athena reflects both the strength of our technical approach and our ability to execute against an ambitious commercialisation roadmap."

Susana Reyes, Vice President for Chamber and Plant Design at Xcimer Energy, added: "A commercially attractive power plant looks very different from a scientific breakthrough facility. We are designing Athena to run continuously at a repetition rate of up to 1 Hz, and the use of a liquid wall chamber maximises availability by protecting the solid structures from the fusion reaction emissions over the entire plant lifetime.

"One reason other fusion chamber designs face a durability problem is that they put solid material where the fusion neutrons go. We don't. The molten salt curtain absorbs and moderates the flux, breeds fuel, and carries the heat - and it flows, so it renews itself continuously. We designed Athena around that property from day one, and it shapes everything: the materials choices, the thermal management, the maintenance philosophy, the economics. And Xcimer's laser architecture uniquely enables this design."

The DOE's acceptance of the Athena design follows Xcimer's completion of earlier programme milestones during the first 18-month budget period in the milestone programme. The company said its next phases of work include full-scale subsystem testing, engineering validation, and preparation for an integrated plant demonstration.

Xcimer published its roadmap to commercialising laser-inertial fusion in February this year.

"The milestone positions Xcimer among the front runners to commercialise fusion energy and marks one of the industry's most comprehensive government reviews of a privately developed fusion plant architecture," the company said. "The acceptance of both the design and roadmap also reflects continued progress under the DOE's Fusion Milestone Development Program and validates Xcimer's roadmap for translating laboratory fusion breakthroughs into a commercially deployable energy system."

Xcimer was one of eight companies selected by DOE in June 2023 to share USD46 million in funding from the Milestone-based Fusion Development Program, with the aim that "within five to 10 years" they "will resolve scientific and technological challenges to create designs for a fusion pilot plant". Xcimer said it had been awarded USD9 million.

Last week, Xcimer announced the launch of operations of its prototype laser system, code-named Phoenix – the largest privately owned laser system in the world and the company's prototype for commercialising laser fusion. Phoenix, housed in Xcimer's Denver laser facility, is a proof of concept for an unconventional fusion architecture: a krypton fluoride excimer laser using Stimulated Brillouin Scattering (SBS) to compress a microsecond-long pulse into the nanosecond timescales fusion requires. Phoenix is designed to demonstrate end-to-end integrated operation of excimer amplification and SBS pulse compression.

USA completes final deliveries for ITER's central solenoid

 SCI-FI-TEK  70YRS IN THE MAKING

Tuesday, 28 April 2026

US ITER has completed final deliveries for the central solenoid magnet for the International Thermonuclear Experimental Reactor under construction in Cadarache, southern France.
 

Five of the central solenoid's six modules have so far been stacked (Image: ITER Organization)

The most recent deliveries included busbars and leads for electrical connections between the modules; earlier, all magnet modules, support structures, and tooling components had been delivered.

The central solenoid magnet consists of six individual sections, or modules, each wound from about 6 kilometres of niobium-tin superconducting cable and weighing more than 122.5 tonnes. Each module required more than two years to fabricate, followed by testing, and then shipment to France. As part of ITER's strategy to build redundancy into mission-critical systems, a full spare module was manufactured to reduce technical and schedule risk. It will be deployed only if a problem emerges with one of the six modules already on site. The 15-year project to produce the modules was completed inside General Atomics' Magnet Technologies Center in Poway, California.

The 18-metre-tall, 4.25-metre-wide magnet is now under assembly at the ITER site. Five of six modules are stacked, with the final module - delivered in September - to be added later this year. Assembly is the responsibility of the ITER Organization, with additional technical support provided through an agreement with the US ITER project team based at Oak Ridge National Laboratory.

Once all six modules are in place, a compression structure, tasked with applying downward precompression on the module stack, will be put in place. The completed central solenoid will then remain on its platform in the Assembly Hall until all nine vacuum vessel sector modules are installed, and then will be moved into the centre of the tokamak pit.

US ITER has also delivered the 'exoskeleton' support structure that will enable the central solenoid to withstand the extreme forces it will generate. The exoskeleton is comprised of more than 9000 individual parts, manufactured by eight US suppliers.

ITER's central solenoid will generate most of the magnetic flux charge of the plasma, initiating the initial plasma current and contributing to its maintenance.

"The completion of the central solenoid magnet highlights the capability of the United States to design and deliver the world's most complex fusion systems," said Kevin Freudenberg, US ITER Interim Project Director. "Congratulations to the entire team who contributed, including those here at Oak Ridge National Laboratory who led the work, and our suppliers who fabricated critical components."

ITER's magnetic system consists of toroidal and poloidal magnetic field coils, correction coils, and the central solenoid. This is the largest superconducting system ever created. The fully assembled pulsed magnetic system will weigh almost 3000 tonnes.

ITER is a major international project to build a tokamak fusion device designed to prove the feasibility of fusion as a large-scale and carbon-free source of energy. The goal of ITER is to operate at 500 MW (for at least 400 seconds continuously) with 50 MW of plasma heating power input. It appears that an additional 300 MWe of electricity input may be required in operation. No electricity will be generated at ITER.

Thirty-five nations are collaborating to build ITER - the European Union is contributing almost half of the cost of its construction, while the other six members (China, India, Japan, South Korea, Russia and the USA) are contributing equally to the rest. Construction began in 2010 and the original 2018 first plasma target date was put back to 2025 by the ITER council in 2016. However, in June 2024, a revamped project plan was announced which aims for "a scientifically and technically robust initial phase of operations, including deuterium-deuterium fusion operation in 2035 followed by full magnetic energy and plasma current operation".

SCI-FI-TEK 70 YRS IN THE MAKING

Expanding America’s role in fusion systems in France and Japan

PPPL’s Luis Delgado-Aparicio will lead a project to provide essential measurement equipment for two doughnut-shaped fusion devices: WEST and JT‑60SA

Princeton University

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From left: James Barton, Luis Delgado-Aparicio, Kajal Shah, Masayuki Ono, Sunny Nyhus and Jasmine Thomas pose with the shipping crates containing PPPL's X-ray imaging crystal spectrometer before the system is flown to Japan. 

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Harnessing fusion energy requires seeing deep inside the plasma that fuels the reaction to understand its behavior. But it’s challenging to catch a glimpse. Custom technology is needed to measure particles hotter than the sun, many times per second.

A new international project will add powerful new X‑ray imaging systems to fusion experiments in France and Japan, along with a multi‑energy camera system in France, to make those measurements and help guide the design of future fusion systems. 

The effort is led by the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL), a global leader in fusion research, working with partners at Massachusetts Institute of Technology (MIT), the University of Tennessee, Knoxville (UTK) and host laboratories overseas. R-V Industries, a private company based in Honey Brook, Pennsylvania, built and tested many of the system’s parts, including the vacuum chambers, stands, mounts and bellows.

“This investment marks a critical step toward advancing our U.S. Fusion Science & Technology Roadmap and the Genesis Mission,” said Jean Paul Allain, Director of the Office of Fusion at DOE. “The high-quality data generated will be invaluable for model validation and verification, while also advancing our efforts to converge artificial intelligence and fusion data, supporting the DOE’s Genesis Mission through the AI-Fusion Digital Convergence Platform.”

DOE has provided $12.5 million in funding for the project, with PPPL staff stationed abroad for several years. International partners often turn to PPPL for the Lab’s unparalleled theory, computation and diagnostic techniques, adding rich value to the overall fusion landscape. As PPPL marks its 75th anniversary this year, the project highlights how the Lab’s legacy of discovery continues to shape the future of fusion energy around the world. 

“This is a strong example of scaling up the capability of the Lab and the U.S. program through international partnership on a major international facility," said Matthew Lanctot, acting research division director for the DOE’s Fusion Energy Sciences.

Seeing the whole plasma

At the tungsten (W) Environment in Steady-state Tokamak (WEST), PPPL and MIT are adding two new X-ray imaging crystal spectrometer (XICS) systems to look through the top and bottom of the plasma, adding to an existing French system that looks through the center. Because these new views avoid the central axis of the doughnut-shaped plasma, scientists call them ‘off-axis’ — and they’re essential for seeing the full picture. The additional systems will let researchers look at the plasma from more angles and with greater precision. Such a view is critical for understanding how plasma behaves and, ultimately, how to produce a sustained fusion reaction.

“If you think of the plasma like a human body, if you only look at the belly button, then you don’t know what’s happening with the head or the feet,” said PPPL’s head of advanced projects Luis Delgado-Aparicio, who leads the project. “Now we will be completing the picture, so we can study the entire body.”

What is XICS? XICS measures X-rays emitted by plasma to determine critical information, including temperature, flow speed and direction, along with the density of unwanted particles that can cool the plasma. These measurements are essential to keeping the fusion reaction stable. There are other systems that can gather such measurements, but they can sometimes provide inaccurate measurements if the temperature shifts. XICS’ advanced calibration system ensures every measurement is highly accurate.

Ultimately, the expanded and improved view provided by XICS will allow for a better understanding of how plasma behaves inside a fusion system like WEST, which is operated by France’s Alternative Energies and Atomic Energy Commission in partnership with the EUROfusion consortium. It is one of many fusion systems worldwide known as a tokamak: a doughnut-shaped device that confines a plasma using magnetic fields. WEST is particularly interesting to study because its walls are made of tungsten, a material many fusion researchers believe is the best choice in terms of longevity and plasma management.

MIT is implementing the two off-axis XICS systems, which will show how temperature, rotation and tungsten impurity levels vary across the entire plasma — not just at one point, but mapped from the plasma’s core to edge. “This is crucial information for all heat, momentum and impurity transport studies,” said John Rice, a senior research scientist at MIT’s Plasma Science and Fusion Center.

Managing heat for future fusion systems

Delgado‑Aparicio and PPPL staff research scientist Tullio Barbui are also designing a new vertical multi-energy soft X-ray camera to pair with an existing horizontal camera on WEST. Much like XICS, the vertical multi-energy camera will provide insights into managing the heat inside a tungsten-clad tokamak. 

“Using the data produced by the multi-energy suite and by XICS, we’re going to all work together to understand particle transport, plasma confinement and radiation management and, ultimately, manage power loss so that fusion systems can run efficiently,” said Delgado‑Aparicio.

Livia Casali, an assistant professor, Zinkle Fellow and ITER scientist fellow at UTK, will design and execute experiments to test impurity behavior. The measurements from the new PPPL spectrometer will provide detailed constraints on radiation and impurity transport. Casali will then use her novel computer code, SICAS, to analyze the experimental data gathered in WEST and the tokamak JT-60SA which is in Naka, Japan. “Impurities affect radiation and temperature, which, in turn, modify plasma conditions that then alter impurity behavior,” Casali said. “SICAS captures this feedback loop consistently, producing a clear and unified view of the whole plasma system.” Casali’s code simulates ion and impurity transport across the entire plasma system within an integrated framework that allows each region to dynamically influence the others. 

Testing advanced scenarios on JT‑60SA

JT‑60SA, a tokamak operated by Japan’s National Institutes for Quantum Science and Technology in collaboration with Europe’s Fusion for Energy, will also receive a 3.3‑metric‑ton XICS system designed and built by PPPL. The XICS system has already been packed into seven large crates for shipment and will be installed and tested over the next two years, with the first data expected in September 2026.

The project will involve significant international collaboration and data sharing, with PPPL researchers working in Japan for the next four years. The project is just one way that PPPL continues to amplify its impact through partnerships with companies, universities and labs across the U.S. and the world.

“This project ties together what we learn on WEST and JT‑60SA and feeds it directly into PPPL’s broader tokamak program,” said Rajesh Maingi, head of tokamak experimental science at PPPL, who serves as the project’s formal monitor. “It’s a model for how U.S. laboratories can contribute high‑impact diagnostics to international facilities.”

Livia Casali, an assistant professor, Zinkle Fellow and ITER research scientist fellow at WEST, is pictured in Cadarache, France. 

Credit

Photo courtesy of Livia Casali / UTK

DOE Under Secretary for Science Darío Gil is pictured (fifth from left) in Japan, with the opened crates containing PPPL’s X-ray imaging crystal spectrometer. 

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Sunny Nyhus / PPPL

PPPL, QST and RVI staff meet to do final vacuum tests of the X‑ray imaging system at RVI in Honey Brook, PA.

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Sunny Nyhus / PPPL

About PPPL

PPPL is mastering the art of using plasma — the fourth state of matter — to solve some of the world’s toughest science and technology challenges. Nestled on Princeton University’s Forrestal Campus in Plainsboro, New Jersey, our research ignites innovation in a range of applications, including fusion energy, nanoscale fabrication, quantum materials and devices, and sustainability science. The University manages the Laboratory for the U.S. Department of Energy’s Office of Science, which is the nation’s single largest supporter of basic research in the physical sciences. Feel the heat at https://energy.gov/science and https://www.pppl.gov.