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<title>New modeling tool advances grid reliability</title>
<description><figure><img alt="Illustration of the RE-INTEGRATE grid modeling tool that has a close up image of what the grid looks like before and after a blackout in the grid over Augusta, Georgia" width="1024" height="574" src="https://www.ornl.gov/sites/default/files/styles/large/public/2025-09/Re-integrate%20grid%20modeling%20tool.jpg?itok=tjGmYIhx" referrerpolicy="no-referrer"></figure>
<p>Covering half of North America, the U.S. electric grid functions somewhat like a vast, complex organism. Researchers at the Department of Energy’s Oak Ridge National Laboratory have developed a new simulation platform for understanding and predicting the behavior of this modern grid. Using a combination of mathematical tools, automation and analysis, the approach provides highly accurate results with less computing time at a lower cost, increasing the reliability of electricity.</p><p>Simulation uses mathematical approaches to reproduce the dynamics of a real-world system. This allows utilities and planners to analyze grid management methods without any risk to safety, equipment or electrical service. ORNL researchers refined a cutting-edge grid modeling approach called Electromagnetic Transient simulation (EMT), which is especially effective for analyzing the split-second reactions of modern power electronics. This capability helps operators prevent cascading blackouts and unsafe operating conditions in modern electric grids brimming with power electronics.&nbsp;</p><p>“We are trying to understand electronics and systems in a way that mimics their real behavior with higher fidelity,” said ORNL researcher Phani Marthi. “The challenge today is that high-fidelity EMT simulation is extremely time-consuming to simulate large-scale modern power grid systems.”&nbsp;</p><p>The ORNL simulation approach is tackling those challenges, as Marthi and his co-authors explained in a <a href="https://www.ornl.gov/sites/default/files/2025-09/RE_INTEGRATE_DAE_Solvers.pdf">paper that was presented in the best paper session at the July general meeting of the IEEE Power and Energy Society</a>.</p><p>Representing the next phase of <a href="https://www.ornl.gov/news/new-software-provides-advanced-grid-simulation-capabilities">ORNL’s national leadership</a> in EMT simulation, the ORNL tool is called RE-INTEGRATE for its enhanced speed and accuracy at simulating large-scale power systems that integrate many power electronics.&nbsp;</p><p>In the past, the grid relied on the natural momentum of huge rotating mechanical machines and power flowing in a single direction along established paths, like a locomotive on a track. But today, power electronics make the grid respond more like a sports car, with rapid electronic adjustments instead of built-in momentum. Unfortunately, today’s grid is not fully ready for that speed. RE-INTEGRATE helps utilities map the best route for the grid of the future.&nbsp;</p><p>Power electronics accommodate generating and moving electricity in different ways. They can also enable both alternating and direct current in long-distance power transmission. This could expand the capacity of the U.S. grid to support a growing population and economy, including new industries such as data centers for AI and cryptocurrency.&nbsp;</p><p>Unlike existing EMT models, RE-INTEGATE is intended as an open-source platform that incorporates features such as numerical simulation techniques, automation and intelligence based on neural networks that function more like the brain for faster computation. These features offer unique advantages over existing tools in analyzing modern grids.&nbsp;</p><p>Eventually the tool will be able to replicate faults — disruptions in the power grid caused by equipment failure, short circuits, or other technical issues — like the one that wiped out power to much of Spain and Portugal in April. “Analysis with the RE-INTEGRATE tool can give us new insights into how to consistently prevent or stop cascading blackouts and brownouts,” Marthi said.</p><p>One of the fundamental building blocks of RE-INTEGRATE is differential algebraic equation solvers. These algorithms reduce the degree of manual processing required for an immense volume of data. As a proof of concept, ORNL researchers validated the effectiveness of these solvers on simple power electronics circuits.&nbsp;</p><p>The long-term goal is honing the software to simulate all possible circumstances that could arise from fast-acting power electronics systems interacting with grid components in a large-scale power grid, equivalent to the grid of the eastern United States.</p><p>This will broaden the accuracy benefits of EMT while enabling greater understanding of how the parts of the broader grid affect each other across service areas and regions.</p><p>"Beyond accelerating the EMT simulation, the next major challenge lies in managing and sifting through the huge volumes of data generated by EMT simulations," Marthi said. ORNL researchers are already developing advanced analysis techniques, including the use of specialized neural networks, so that the RE-INTEGRATE tool can enhance power system operations and support informed decision-making. “We want to create an entire EMT ecosystem with RE-INTEGRATE as the backbone, including all these capabilities so utilities use it more often and with more confidence.”&nbsp;</p><p>Researchers who contributed to the development of automation and solvers for RE-INTEGRATE include ORNL researchers Jongchan Choi and Suman Debnath with support from student Soumyajit Gangopadhyay and intern Kuan-Chieh Hsu.&nbsp;The project was funded by the DOE Office of Electricity.</p><p>RE-INTEGRATE advances will be presented during&nbsp;an EMT simulation workshop at ORNL, co-hosted by the North American Electric Reliability Corporation Oct. 7-9 in Knoxville, Tennessee.&nbsp;</p><p>UT-Battelle manages ORNL for the Department of Energy’s Office of Science, the single largest supporter of basic research in the physical sciences in the United States. The Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit&nbsp;<a href="https://energy.gov/science"><strong>energy.gov/science</strong></a>.&nbsp;</p><h3><strong>Learn more about related grid modeling research:&nbsp;</strong></h3><ul><li><a href="https://www.ornl.gov/news/new-software-provides-advanced-grid-simulation-capabilities">New software provides advanced grid simulation capabilities</a></li><li><a href="https://www.ornl.gov/news/ornl-demonstrates-power-new-modeling-approach-understand-faults-modern-electric-grid">ORNL demonstrates power of new modeling approach to understand faults in the modern electric grid</a></li></ul>
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<link>https://www.ornl.gov/news/new-modeling-tool-advances-grid-reliability</link>
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<pubDate>Tue, 30 Sep 2025 12:00:00 GMT</pubDate>
<author>Phani Ratna Vanamali Marthi, Jongchan Choi, Suman Debnath, Soumyajit Gangopadhyay</author>
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<title>Decades-old graphite moderation question answered</title>
<description><figure><img alt="An optical microscopy image of nuclear grade PCEA graphite captured at ORNL demonstrates the tiny pores, voids, and cracks that are inherent to this form of graphite. " width="768" height="768" src="https://www.ornl.gov/sites/default/files/styles/large/public/2025-09/Optical%20microscopy.jpg?itok=qH8AtbTx" referrerpolicy="no-referrer"></figure>
<p>A remarkable study led by Oak Ridge National Laboratory answers a decades-old question in nuclear science: Do tiny pores in graphite affect nuclear reactor performance? &nbsp;</p><p>The answer,&nbsp;<a href="https://www.sciencedirect.com/science/article/abs/pii/S0008622325006359?via%3Dihub">published in the journal&nbsp;</a><a href="https://gcc02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.ornl.gov%2Fpublication%2Fporosity-nuclear-graphite-and-its-impact-nuclear-reactor-science-and-criticality-safety&amp;data=05%7C02%7Cmccroryea%40ornl.gov%7C87e1918a22cc43e2b83e08ddd9d0d5aa%7Cdb3dbd434c4b45449f8a0553f9f5f25e%7C1%7C0%7C638906213141091574%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&amp;sdata=1RH18Zd0dluaqYig3Gjb0y6nuOx4Z9Yu1tepW2EkVOQ%3D&amp;reserved=0"><em>Carbon</em></a>, is clear: Graphite’s natural porosity does not affect its performance as a moderator of nuclear reactions.&nbsp;</p><p>Graphite’s ability to withstand high temperatures makes it an ideal material for sustaining nuclear reactions in nuclear reactors. Understanding its composition is essential for simulating how reactors maintain steady, controlled nuclear reactions. ORNL’s research confirms that the tiny cracks and voids in graphite do not disturb the atomic vibrations that determine its interactions with neutrons. This finding offers reactor developers greater confidence that graphite will perform its moderation duties as expected.&nbsp;</p><p>“This work highlights the power of pairing cutting-edge modeling with world-class facilities like the Spallation Neutron Source and High Flux Isotope Reactor to resolve a complex and important question for nuclear energy,” said ORNL’s Kemal Ramić.&nbsp;&nbsp;</p><p>Resolving this decades-old question strengthens the nation’s leadership in nuclear science and reactor design.<br><br>This work was performed under the framework DOE/NRC Collaboration for Criticality Safety Support for Commercial-Scale HALEU Fuel Cycles and Transportation (DNCSH) project.&nbsp;</p>
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<link>https://www.ornl.gov/news/decades-old-graphite-moderation-question-answered</link>
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<pubDate>Tue, 30 Sep 2025 12:00:00 GMT</pubDate>
<author>Kemal Ramic</author>
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<title>Fluid flow simulation on Frontier earns Gordon Bell finalist selection</title>
<description><figure><img alt="Illustration of a simulated a 33-engine configuration, focusing on the interacting exhaust plumes" width="1024" height="463" src="https://www.ornl.gov/sites/default/files/styles/large/public/2025-09/Gordon%20Bell%20Nomination.jpg?itok=ZCgpfutL" referrerpolicy="no-referrer"></figure>
<p>Using a new computational technique called information geometric regularization (IGR) researchers from the Georgia Institute of Technology and the Courant Institute of Mathematical Sciences at New York University conducted the largest-ever computational fluid dynamics (CFD) simulation of fluid flow on the Frontier supercomputer at the Department of Energy’s Oak Ridge National Laboratory.</p><p>Their undertaking — and the methods behind it — earned the team a finalist selection for the&nbsp;<a href="https://awards.acm.org/bell">Association for Computing Machinery’s 2025 Gordon Bell Prize</a> for outstanding achievement in high-performance computing (HPC).</p><p>“It’s exciting to link a grand challenge scientific problem to an interesting new method, with an implementation tailored for the latest supercomputer architectures,” said Spencer Bryngelson, an assistant professor in Georgia Tech’s College of Computing who led the project with Florian Schäfer, an assistant professor at the Courant Institute.</p><p>CFD simulations are often used to predict the behaviors of new aircraft designs, showing the potential interactions of proposed rockets and airplanes — and their engines — with the atmosphere. In this CFD study, Bryngelson and his team used their open-source&nbsp;<a href="https://www.olcf.ornl.gov/2025/02/11/the-olcfs-problem-busters/">Multicomponent Flow Code</a>&nbsp;(available under the MIT license&nbsp;<a href="https://github.com/MFlowCode/MFC">on GitHub</a>) to examine rocket designs that feature clusters of engines. Predicting how all those engines’ exhaust plumes may interact upon launch will help rocket designers avoid mishaps — especially with the scale and speed afforded by the Georgia Tech team’s method.</p><p>The team used Frontier to simulate a 33-engine configuration, like the one used by the SpaceX Starship Super Heavy Booster, reflecting the aerospace industry’s move toward first-stage multi-engine layouts in rocket design. The flow from the individual engines was modeled at 10 times the speed of sound, a regime at which gases behave violently and unpredictably due to extreme pressure and temperature shifts. This simulation achieved a resolution of over 200 trillion grid points, or 1 quadrillion degrees of freedom (variables that must be solved).</p><p>The methodology was optimized to use the unified CPU-GPU memory on Frontier and achieve a step-change increase in resolution and scale over previous record-holding CFD simulations. At the same time, the team achieved a 4 times faster time to solution and increased energy efficiency by 5.7 times over current state-of-the-art numerical methods.</p>
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<link>https://www.ornl.gov/news/fluid-flow-simulation-frontier-earns-gordon-bell-finalist-selection</link>
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<pubDate>Tue, 30 Sep 2025 12:00:00 GMT</pubDate>
<author>Reuben Budiardja</author>
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<title>Frontier simulations pierce mysteries of galactic nuclei</title>
<description><figure><img alt="Illustration of galaxy clusters in teal and blue colors are splattered across the image" width="1024" height="576" src="https://www.ornl.gov/sites/default/files/styles/large/public/2025-09/OLCF_GalaxyClusters.jpg?itok=D2UZ3hV_" referrerpolicy="no-referrer"></figure>
<p>To probe the mysteries of how galaxies evolve over time, scientists needed a supercomputer with out-of-this-world computational power.</p><p>The results of a&nbsp;<a href="https://iopscience.iop.org/article/10.3847/1538-4357/adde45">study</a>&nbsp;conducted on the&nbsp;<a href="https://www.olcf.ornl.gov/frontier/">Frontier</a>&nbsp;supercomputer at the Department of Energy’s Oak Ridge National Laboratory offer the clearest portrait so far of how some galaxies regulate the energy produced by supermassive black holes at their cores.</p><p>These black holes — which range up to billions of times the sun’s mass — power phenomena known as&nbsp;<a href="https://webbtelescope.org/contents/articles/what-are-active-galactic-nuclei">active galactic nuclei</a>, which constantly pump heat, dust and gas into their environments. Some of that material orbits the nuclei in luminous regions known as&nbsp;<a href="https://webbtelescope.org/glossary.html#h3-CK-4cdc440b-71cf-45e8-a6e6-7c76622d19aa">accretion disks</a>, while some wanders far beyond galactic bounds.</p><p>“Fundamentally, we set out to understand how these galaxies regulate themselves over the age of the universe,” said Brian O’Shea, a computational astrophysicist at Michigan State University and co-author of the study. “These galaxy clusters are the biggest things in the universe, millions of light-years across, with black holes at their centers that are bigger than our entire solar system. All the heat and material are being ejected and recycled from each nucleus as jets into the galactic atmosphere.</p><p>“We wanted to find out: Where do the energy and material end up? How does that energy and turbulence feed into the galactic structures and their formation? And how do these systems keep radiating all this heat for billions of years without collapsing on themselves? We’ve never been able to even attempt to answer these questions before at this level of fidelity because we never had a machine like Frontier.”</p><p>The Frontier study used as its test case a black hole of about 10<sup>9</sup> solar masses, or a billion times the size of the sun, at the center of a galaxy cluster of about 10<sup>15</sup> solar masses, or a quadrillion times the size of the sun — and about a thousand times the mass of the Milky Way galaxy that’s home to Earth. The study simulated the cluster’s evolution over billions of years, modeling each step of the various jet activity cycles.</p><p>“These jets are extremely fast, so fast that even with Frontier’s power we had to artificially limit their speed in the simulation to about 5% of the speed of light,” said Philipp Grete, a computational astrophysicist at the Hamburg Observatory in Germany. “That still resulted in the simulations taking about 2 million steps to complete.”</p><p>The team ran a&nbsp;<a href="https://xmagnet-simulations.github.io/">series of simulations</a>&nbsp;that tested a wide range of model assumptions. The process required 700,000 node hours and 17,088 GPUs using&nbsp;<a href="https://github.com/parthenon-hpc-lab/athenapk">AthenaPK</a>, an open-source, astrophysical magnetohydrodynamics code based on the&nbsp;<a href="https://github.com/parthenon-hpc-lab/parthenon">Parthenon</a>&nbsp;framework. The number of steps, the long timespan and the sheer amount of detail revealed by the simulations couldn’t have been accomplished on any other machine.</p><p>“One of the long-standing questions we’ve had is whether these systems can stay stable across billions of years,” Grete said. “But a big challenge for us has always been just keeping the system evolving long enough to observe everything and understand the details. The only way to do this at all was on a machine not just with lots of memory plus storage to host the data but with enough GPU computing power to deliver a fast turnover. That’s why we could only do these kinds of simulations on Frontier.”</p><p>Frontier’s nearly 2-exaflop speeds — equal to 2 quintillion calculations per second — enabled the team to zero in on key details never before simulated, including the gradual formation of gas filaments. Similar filaments surround such well-known astronomical features as the <a href="https://science.nasa.gov/asset/hubble/dss-perseus-galaxy-cluster/">Perseus galaxy cluster</a>, a group of more than 1,000 galaxies about 240 million light-years from Earth.</p><p>“We’re the first study ever to reproduce this phenomenon,” O’Shea said. “Because these galaxy clusters are so big, we couldn’t watch these filaments evolve before. Their formation had been a mystery, but now we know how they come to be: through the turbulence created by the interaction of these cold gases with the hot intergalactic plasma — some of it as hot as 100 million Kelvins — and the magnetic fields that surround them.”</p><p>The results ultimately showed galaxy clusters rely on those magnetic fields to regulate their energy and remain stable over time. The team hopes to expand on the study to incorporate additional physics such as cosmic rays and other plasma phenomena.</p><p>“We’re just beginning to unpack the role played by the interaction between these fields and the turbulent plasma,” O’Shea said. “As we increase our understanding of these phenomena, there could be lessons learned that apply not just to galaxy clusters but to supernovae and even to the turbulence found in fusion tokamaks. The more closely we can analyze this data, the more secrets of these complex systems we can unravel.”</p><p>Besides Grete and O’Shea, the research team included Mark Voit and Benjamin Wibking of&nbsp;Michigan State University,&nbsp;Deovrat Prasad&nbsp;of&nbsp;Cardiff University, Forrest Glines&nbsp;of&nbsp;NVIDIA, and Marcus&nbsp;Brüggen and&nbsp;Martin Fournier&nbsp;of the&nbsp;University of Hamburg.</p><p>Support for this research came from the National Science Foundation, the National Aeronautics and Space Administration, the DOE Office of Science Advanced Scientific Computing Research program and the German Research Foundation. The OLCF is a DOE Office of Science user facility at ORNL.</p><p>Publications related to this research include:</p><ul><li>&nbsp;“The XMAGNET Exascale MHD Simulations of SMBH Feedback in Galaxy Groups and Clusters: Overview and Preliminary Cluster Results,” <em>The Astrophysical Journal</em>,&nbsp;<a href="https://iopscience.iop.org/article/10.3847/1538-4357/adde45">https://doi.org/10.3847/1538-4357/adde45</a>.</li><li>“XMAGNET: Velocity Structure Functions of Active Galactic Nucleus-Driven Turbulence in the Multiphase Intracluster Medium,” <em>Astronomy &amp; Astrophysics</em>,&nbsp;<a href="https://www.aanda.org/articles/aa/full_html/2025/06/aa54278-25/aa54278-25.html">https://doi.org/10.1051/0004-6361/202554278</a>.</li><li>“The Properties of Magnetised Cold Filaments in a Cool-Core Galaxy Cluster,” <em>Astronomy &amp; Astrophysics</em>,&nbsp;<a href="https://doi.org/10.1051/0004-6361/202451031">https://doi.org/10.1051/0004-6361/202451031</a>.</li></ul><p>UT-Battelle manages ORNL for DOE’s Office of Science, the single largest supporter of basic research in the physical sciences in the United States. The Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit energy.gov/science. – <em>Matt Lakin</em></p>
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<link>https://www.ornl.gov/news/frontier-simulations-pierce-mysteries-galactic-nuclei</link>
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<pubDate>Tue, 30 Sep 2025 12:00:00 GMT</pubDate>
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<title>Unlocking ceramic 3D printing for next-generation chemical reactors</title>
<description><figure><img alt="From left, Corson Cramer, Trevor Aguirre and Amy Elliott discuss the silicon carbide gyroid component, which was 3D printed using the binder jet printer displayed in the background. " width="1024" height="683" src="https://www.ornl.gov/sites/default/files/styles/large/public/2025-09/ASB_0065%20%281%29.jpg?itok=qLWynzKz" referrerpolicy="no-referrer"></figure>
<p>In collaboration with chemical technology and engineering company Dimensional Energy, scientists at the U.S. Department of Energy’s Oak Ridge National Laboratory have integrated binder jet additive manufacturing with an advanced post-processing method to fabricate leak-tight ceramic components, overcoming a key challenge of ceramic additive manufacturing.</p><p>While ceramic components perform exceptionally well in extreme environments — exhibiting high temperature resistance, chemical stability and mechanical strength — current methods of ceramic 3D printing fall short on scalability. This shortcoming limits their use in critical applications such as high-throughput chemical reactors, which are used for pharmaceutical or chemical processing, where large, leak-proof parts are essential.&nbsp;</p><p>ORNL’s innovative solution provides a scalable method for creating complex ceramic structures by leveraging a robust joining technique that enables smaller 3D-printed pieces to be assembled to create the needed components.</p>
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<link>https://www.ornl.gov/news/unlocking-ceramic-3d-printing-next-generation-chemical-reactors</link>
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<pubDate>Fri, 26 Sep 2025 12:00:00 GMT</pubDate>
<author>Trevor Aguirre, M. Dylan Richardson, Corson Cramer, Amy Elliott, Kashif Nawaz</author>
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<title>New results from physics experiment at ORNL show no sign of sterile neutrinos</title>
<description><figure><img alt="The PROSPECT neutrino detector in a lab at Oak Ridge National Laboratory, with pipes overhead and a nitrogen tank nearby. " width="875" height="500" src="https://www.ornl.gov/sites/default/files/styles/large/public/2025-09/edit_PROSPECT_at_HFIR%20%281%29.jpg?itok=nR6pzZyT" referrerpolicy="no-referrer"></figure>
<p>Neutrinos, elusive fundamental particles, can act as a window into the center of a nuclear reactor, the interior of the Earth, or some of the most dynamic objects in the universe. Their tendency to change "flavors" may provide clues into the prominence of matter over antimatter in the universe or explain the existence of dark matter.</p><p>Physicists are particularly interested in proving the existence of “sterile” neutrinos. Their discovery would reveal a new form of matter that interacts only with gravity and could influence the universe's evolution.</p><p>In a new study published in&nbsp;<a href="https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.134.151802">Physical Review Letters</a>, a team of researchers from U.S. universities and national laboratories has set stringent limits on the existence and mass of sterile neutrinos. While they have yet to find the particles, they now know where&nbsp;<em>not</em>&nbsp;to look.</p><p>The collaboration analyzed data from the PROSPECT-I detector, stationed near the High Flux Isotope Reactor, or HFIR, at the Department of Energy’s Oak Ridge National Laboratory, or ORNL. In the nuclear reactor core, the fission process releases electron antineutrinos.</p><p>Neutrinos and antineutrinos come in three known “flavors,” and strangely, they can switch between them as they propagate through space. This oscillation phenomenon shows neutrinos have a tiny, but nonzero, mass. They interact through the weak nuclear force and gravity. In contrast to these three known flavors, sterile neutrinos would only interact via gravity. Some theories predict their existence, and persistent hints in anomalous experimental data may support their presence.</p><p>“If these new sterile neutrino types exist, then the neutrinos generated by the reactor will have some probability to transform into this sterile type as they propagate from the reactor to the detector,” said Bryce Littlejohn, a professor at Illinois Tech and one of the paper’s 47 authors. “If that were to occur, PROSPECT would detect fewer reactor-produced neutrinos than expected, since a sterile neutrino would not interact in the detector.”</p><p>PROSPECT is unique because it is close to a compact nuclear reactor core. It can search for sterile neutrinos with high mass values relative to other experiments that are further from larger reactors.&nbsp;In doing so, it has placed the strongest limits of any reactor experiment in a high-mass region and disfavors the possibility that anomalous results in recent Russian reactor and radioactive source neutrino experiments are due to sterile neutrinos.</p><p>“These results, tapping the full potential of the dataset from PROSPECT, show no unusual signs of neutrinos disappearing on their journey to the detector,” Littlejohn said.</p><p>“The PROSPECT experiment has been very productive, even though it is a relatively small detector and collaboration,” said author Russell Neilson, a professor at Drexel University. “Unique features of the experiment have resulted in scientific papers on the sterile neutrino, characterizing antineutrino emissions from reactors, and searching for dark matter.” Another recent study even used the detected antineutrino signal to locate the position of the HFIR reactor core, he added.&nbsp;<br><br>This paper is the&nbsp;<a href="https://inspirehep.net/experiments/1409204?ui-citation-summary=true">10th physics publication</a>&nbsp;based on data collected by PROSPECT in 2018. It presents a marked improvement in rejecting background noise and efficient data use compared to earlier results probing the existence of sterile neutrinos.&nbsp;</p><p>“The PROSPECT-I detector experienced some technical problems that limited earlier results. At LLNL, we led the development of a technique to extract more information from the data, greatly improving background rejection,” said author Nathaniel Bowden, a physicist at the Department of Energy’s Lawrence Livermore National Laboratory, or LLNL. “Studies like these give us important insights that also advance our work on national security — for example, building sensitive neutron detectors or using antineutrinos to monitor nuclear reactor operations.”</p><p>“The UTK/ORNL analysis group, led by my former graduate students Diego Venegas-Vargas, Xiaobin (Jeremy) Lu and Blaine Heffron, has been instrumental in developing and optimizing the dataset used in this result,” said Alfredo Galindo-Uribarri, a distinguished scientist in the Physics Division of ORNL and an adjunct professor in the Department of Physics and Astronomy of the University of Tennessee, Knoxville, or UTK. “They also explored and implemented innovative analysis methods that have resulted in a final dataset demonstrating the full potential of the PROSPECT detector.”</p><p>He added, “In addition to co-leading the current findings on sterile neutrinos, the UTK/ORNL group has spearheaded efforts in producing the most precise measurement of the uranium-235 energy spectrum, developing machine learning-driven methods for antineutrino event reconstruction and introducing novel calibration techniques for future antineutrino detectors.”&nbsp;</p><p>The collaboration is joining forces with two other experiments to extend the search for sterile neutrinos into other mass regimes. The team is also working on an upgrade to the PROSPECT detector that will retain its excellent performance while improving robustness, allowing for a large increase in collected data.</p><p>PROSPECT is supported by the Department of Energy Office of Science and the Heising-Simons Foundation. The researchers also received support from, Drexel University, the Illinois Institute of Technology, the University of Hawai’i, Yale University, Brookhaven National Laboratory, the Laboratory Directed Research and Development program at Lawrence Livermore National Laboratory, the National Institute of Standards and Technology and Oak Ridge National Laboratory. The collaboration also benefits from the support and hospitality of the High Flux Isotope Reactor, a DOE Office of Science User Facility.</p><p>UT-Battelle manages ORNL for DOE’s <a href="https://science.energy.gov/">Office of Science</a>. The single largest supporter of basic research in the physical sciences in the United States, the Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit <a href="https://science.energy.gov/">https://science.energy.gov/</a>.</p><p>— Abridged and adapted from <a href="https://www.llnl.gov/article/52796/search-sterile-neutrinos-continues-nuclear-reactors">a story by Ashley Piccone</a> of Lawrence Livermore National Laboratory, with additional reporting by Dawn Levy of Oak Ridge National Laboratory</p>
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<link>https://www.ornl.gov/news/new-results-physics-experiment-ornl-show-no-sign-sterile-neutrinos</link>
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<pubDate>Thu, 25 Sep 2025 12:00:00 GMT</pubDate>
<author>Chris Bryan, Andrew Conant, Geoffrey G Deichert, Alfredo Galindo-Uribarri, Xiaobin Lu</author>
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<title>Spent nuclear fuel, materials research focus of ORNL awards from NSUF</title>
<description><figure><img alt="ORNL’s Irradiated Fuels Examination Laboratory is a Nuclear Science User Facility designed to perform chemical, physical, and metallurgical examination of nuclear reactor fuel elements and reactor parts. " width="1024" height="683" src="https://www.ornl.gov/sites/default/files/styles/large/public/2025-09/2018-P06742.jpg?itok=D4OI5tr1" referrerpolicy="no-referrer"></figure>
<p>Crucial research needed to inform advancements in nuclear materials and fuel cycle research will soon be underway at the Department of Energy’s Oak Ridge National Laboratory.&nbsp;</p><p>Several ORNL-based projects were selected for <a href="https://nsuf.inl.gov/Home/Article/118?Keyword=&amp;Archive=False">2025 Nuclear Science User Facilities (NSUF) Rapid Turnaround Experiment (RTE) Awards</a>, demonstrating the lab’s unmatched nuclear capabilities that are driving nuclear energy innovation.&nbsp;</p><p>These awards provide researchers access to specialized facilities to perform targeted experiments with the aim of swiftly filling nuclear research gaps. Researchers from across the country and from within ORNL will leverage the lab’s specialized facilities to inform advances in nuclear materials and fuels, as well as spent nuclear fuel storage.&nbsp;</p><h2><strong>How ORNL is strengthening nuclear R&amp;D</strong></h2><p>Yadu Sasikumar, an R&amp;D staff member in the Used Fuel and Nuclear Material Disposition Group, will lead a RTE project&nbsp;<a href="https://www.ornl.gov/publication/sister-rod-destructive-examinations-fy23">expanding on prior research</a> that characterizes how used nuclear fuel is weakened by repeated stress during transport, handling and storage using ORNL’s Irradiated Fuels Examination Laboratory.&nbsp;The IFEL facility is designed to handle commercial spent fuel and perform a wide range of post-irradiation examinations of nuclear fuels.&nbsp;</p><p>“Only when we exactly understand how used nuclear fuel weakens under stress can we ensure its safety and establish better design parameters to transport, store and dispose of it,” Sasikumar said. “We can also inform better engineering of future advanced fuel and cladding designs, making them more robust, predictable and long-lasting from reactor to repository.”</p><p>During the six-month project, Sasikumar’s team will characterize fractures in used fuel samples after mimicking stresses during transport. The analysis will help inform when the bond between the cladding and fuel changes because of repeated cyclic bending and how this impacts the rod’s mechanical properties.&nbsp;</p><p>Sasikumar will work with industry collaborator Matthieu Aumand, a materials engineer at Framatome, a nuclear fuel and reactor manufacturer, as well as ORNL colleagues Paul Cantonwine, group leader for Used Fuel and Nuclear Material Disposition, and Shaileyee Battacharya, postdoctoral research associate.&nbsp;</p><p>ORNL will also host several NSUF awardees from nuclear industry and academia to conduct experiments in the Low Activation Materials Design and Analysis Lab. The LAMDA Lab, a unique space for safely working with low-radiation samples, allows hands-on testing and precise analysis made otherwise impossible in traditional hot cells, which require remote handling. The lab is also equipped with several examination tools to study physical properties and structural data to understand the behavior of materials in nuclear environments.</p><p>NSUF awardees will use the LAMDA Lab for research and testing focused on innovations in fuel cladding, reactor core and pressure vessel materials, fiber optic sensors, and accident tolerant fuels. ORNL researchers Christian Petrie, Dan Sweeney, Maxim Gussev, Caleb Massey and Stephen Taller will serve as co-principal investigators on these efforts, providing operational and technical research support to guest researchers.&nbsp;</p><h2><strong>Why ORNL’s facilities are vital to the future of nuclear energy</strong></h2><p>ORNL’s suite of NSUF facilities, including the High Flux Isotope Reactor, the Irradiated Materials Examination and Testing facility, IFEL and LAMDA, provide world-class capabilities in material irradiation, post irradiation examination and nuclear materials science. Together, they enable neutron and gamma irradiations, in-depth studies of irradiated fuels and materials, and hands-on collaboration with ORNL experts for analysis, data interpretation and research guidance.&nbsp;</p><p>"ORNL’s facilities, combined with our wide range of expertise, are helping researchers tackle big challenges in nuclear energy,” said Kory Linton, ORNL’s senior Nuclear Science User Facility program manager. “It’s this combination of capability and collaboration that keeps ORNL at the forefront of nuclear materials innovation and research.”</p><p>ORNL is committed to supporting U.S. energy needs by pursuing strategic research that advances a wide variety of affordable, abundant and competitive nuclear technologies, and strengthens national security. The lab’s scientific expertise and world-class facilities are often the first step in advancing nuclear energy innovations.</p><p>UT-Battelle manages ORNL for DOE’s Office of Science, the single largest supporter of basic research in the physical sciences in the United States. The Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit&nbsp;<a href="https://www.energy.gov/science/office-science?nrg_redirect=332043">energy.gov/science</a>. <em>– Liz McCrory</em>&nbsp;</p>
</description>
<link>https://www.ornl.gov/news/spent-nuclear-fuel-materials-research-focus-ornl-awards-nsuf</link>
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<pubDate>Wed, 24 Sep 2025 12:00:00 GMT</pubDate>
<author>Yadu Sasikumar, Paul Cantonwine, Shaileyee Bhattacharya, Kory Linton</author>
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<title>Forging fusion: Summit supercomputer study speeds power plant design</title>
<description><figure><img alt="Type One Energy used ORNL’s Summit supercomputer to develop an optimized stellarator fusion power plant concept. Colors indicate the strength of the magnetic field that confines the plasma." width="1024" height="576" src="https://www.ornl.gov/sites/default/files/styles/large/public/2025-09/Type%20one%20energy.png?itok=Kz02gYAF" referrerpolicy="no-referrer"></figure>
<p>The nuclear reactions that fuel the sun could soon be harnessed to generate electricity on Earth — with help from supercomputers at the Department of Energy’s Oak Ridge National Laboratory.</p><p><a href="https://typeoneenergy.com/">Type One Energy Group</a>, a Knoxville-based startup, expects to build the world’s most advanced <a href="https://www.energy.gov/science/doe-explainsstellarators#:~:text=A%20stellarator%20is%20a%20machine,a%20donut%2C%20called%20a%20torus.">stellarator fusion</a> device by 2030, with a pilot power plant to follow that would produce commercial fusion energy by the mid-2030s. The Type One Energy team discussed their pilot plant concept in a <a href="https://www.cambridge.org/core/journals/journal-of-plasma-physics/collections/physics-basis-of-the-infinity-two-fusion-power-plant">series of six papers recently published in the<em> Journal of Plasma Physics</em></a>.</p><p>“We have a target for the pilot plant within the decade, and we expect to have a functional prototype much sooner,” said Walter Guttenfelder, principal scientist for Type One Energy. “The scientific understanding at this point is mature enough to know there are no obvious showstoppers, and we wouldn’t be this far along without the leadership computing machines at ORNL.”</p><p>The prototype, Infinity One, won’t produce electricity but would demonstrate the company’s design works and clear the path for the pilot plant, Infinity Two, which would generate an effective output of 350 megawatts for the electric grid. The detailed modeling offered by ORNL’s <a href="https://www.olcf.ornl.gov/summit/">Summit</a> supercomputer, which has since ceased operations, shaved at least a year off the time from drawing board to reality, the company estimates — maybe more.</p><p>“These sorts of high-fidelity performance projections have never been used before to design a fusion power plant,” said Noah Mandell, a Type One Energy computational scientist. “The scale of Summit was absolutely necessary for these calculations.”</p><h2><strong>The promise of fusion power</strong></h2><p><a href="https://www.energy.gov/science/doe-explainsfusion-reactions">Fusion</a> occurs when two atoms’ nuclei combine to form a single nucleus. The difference in mass between the two fusing nuclei and the one resulting nucleus converts to raw energy. That type of energy powers the sun and stars, and its promise fuels hopes for a potentially unlimited power source for the world.</p><p>But first scientists and engineers must figure out how to make fusion work — safely, reliably and consistently at a mass scale.</p><p>A stellarator uses an intricate set of superconducting electromagnetic coils to confine a plasma made up of the hydrogen isotopes deuterium and tritium at temperatures 10 times hotter than the <a href="https://science.nasa.gov/sun/facts/#:~:text=The%20core%20is%20the%20hottest,centimeter%20(g%2Fcm%C2%B3).">core of the sun</a>. That’s an average temperature of 270 million degrees Fahrenheit, or 150 million degrees Celsius.</p><p>“The sun’s a little too massive for us to have economical fusion on Earth, so we’ve got to go much hotter to make that core small enough to fit here on our planet,” Guttenfelder said. “These machines have been built at the laboratory level, so we know the overall concept can work. The current models just aren’t big enough to produce energy on a commercial scale.”</p><p>The world’s largest stellarator, the <a href="https://www.ornl.gov/news/ornls-pellet-injector-enables-world-record-performance-w7-x">Wendelstein 7-X</a> at the Max Planck Institute for Plasma Physics near Munich in Germany, has a radius of just 5.5 meters, or a little more than 18 feet. Type One Energy engineers expect they’ll need a device about twice that radius to make commercial fusion viable.</p><p>“We know a lot about the right way to get there, but we want to confirm it,” Guttenfelder said. “We need the greatest accuracy possible because we’re projecting to a size that’s never been built. It’s easy to talk in the abstract about orders of magnitude, but in engineering we need to know everything we can at a much smaller tolerance for error so we can reduce risks.”</p><h2><strong>The trouble with nuclear turbulence</strong></h2><p>The main risk to solve? Turbulence — the unstable, chaotic flow of heat and mass within a plasma. Too much plasma turbulence, and the stellarator core could leak energy and fail to reach the necessary temperatures for fusion.</p><p>“Turbulence occurs everywhere, from the flow around airplane wings and cars to <a href="https://www.ornl.gov/news/ornls-pellet-injector-enables-world-record-performance-w7-x">stirring cold cream into hot coffee</a>,” Guttenfelder said. “A great comparison for our purpose is between the turbulence in our devices and the atmospheric turbulence around Earth. As the sun heats the equator more than the poles, that reaction drives airflows and turbulence that dictate the weather patterns from day to day. The same process happens inside the stellarator. We’re losing heat from the core to the edge, and that’s holding us back.”</p><p>That problem traditionally prompts two expensive attempts at a solution: build a bigger machine or generate a stronger magnetic field to contain the plasma.</p><p>The stellarator’s unique flexibility offers a third solution: optimize the stellarator’s shape to keep turbulence under control.</p><p>“What if we could squish or expand Earth’s equator?” Guttenfelder said. “That would disrupt and change the turbulent flow patterns in Earth’s atmosphere. That’s the principle that we needed to explore for the stellarator using modeling and simulation: Can we find an optimized 3D shape to disrupt those turbulent flows inside the stellarator and minimize that leaking of energy so we can sustain a really hot, high-efficiency fusion plasma?”</p><h2><strong>Crafting a stellarator concept</strong></h2><p>The computing power required to simulate that turbulence and predict the stellarator’s performance far surpassed the capabilities of any in-house computer at Type One Energy. The team, which included Type One Energy computational physicist Guillaume Le Bars, turned to the <a href="https://www.olcf.ornl.gov/">Oak Ridge Leadership Computing Facility</a>, home to ORNL’s Summit supercomputer at the time.</p><p>Summit’s high-resolution modeling capabilities helped the Type One Energy team develop the knowledge and tools to make their solution a reality and to confirm an optimized stellarator as an economically viable concept for a fusion power plant.</p><p>Summit’s speeds of 200 petaflops, or 200 quadrillion calculations per second, offered an ideal match for the GX code developed by Mandell with colleagues at the University of Maryland and Princeton Plasma Physics Laboratory. The code, tailored especially for GPUs, solves nonlinear 5D equations that track the behavior of magnetized plasmas.</p><p>“For this study, we ran two families of calculations,” Mandell said. “We ran large ensembles of turbulence simulations, searching for optimal 3D shapes that can keep turbulence under control. Once we found a few shapes we liked, we also ran large, coupled turbulence calculations to make high-fidelity performance predictions, from densities and temperatures of the plasma to the total fusion energy output of the power plant. No one’s ever been able to use turbulence simulations of this kind at these scales to design a fusion device. Summit allowed us to do that.”</p><p>The team, granted 250,000 node hours of simulation on Summit, used the results to pinpoint the most promising design, detailed in the <em>Journal of Plasma Physics</em> study.</p><p>“We’re laser-focused on building our prototype and the pilot plant,” Guttenfelder said. “At the same time, we think there are some areas that deserve further study, so we want that extra level of confidence. Thanks to Summit, we’ve been able to run thousands of evaluations to make our design choice and uncover new areas of interest that deserve further exploration. Summit’s results gave us the confidence to continue to advance and accelerate our chosen design toward the finish line.”</p><p>The team hopes to further refine the design by using <a href="https://www.olcf.ornl.gov/frontier/">Frontier</a> — Summit’s faster, more powerful successor at speeds of roughly 2 exaflops, or 2 quintillion calculations per second.</p><p>Support for this research came from the DOE Office of Science Advanced Scientific Computing Research program. The OLCF is a DOE Office of Science user facility.</p><p>UT-Battelle manages ORNL for DOE’s Office of Science, the single largest supporter of basic research in the physical sciences in the United States. The Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit <a href="http://energy.gov/science">energy.gov/science</a>.</p>
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<link>https://www.ornl.gov/news/forging-fusion-summit-supercomputer-study-speeds-power-plant-design</link>
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<pubDate>Wed, 24 Sep 2025 12:00:00 GMT</pubDate>
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<title>Thornton named Fellow of the American Geophysical Union</title>
<description><p>Peter Thornton, a Corporate Fellow and head of the Earth Systems Science Section at the Department of Energy’s Oak Ridge National Laboratory, has been named a Fellow of the American Geophysical Union (AGU).</p><p>Established in 1919, the AGU is a global community of more than half a million professionals and advocates in the Earth and space sciences. The AGU Fellows program recognizes members who have made exceptional contributions to Earth and space science through a breakthrough, discovery or innovation in their field. Fellows comprise less than 0.1% of AGU members, and act as external experts, capable of advising government agencies and other organizations.&nbsp;</p><p>Thornton’s research at ORNL seeks a greater understanding of Earth processes using innovative modeling techniques to simulate the interactions of land ecosystems with all other components of the Earth system, including biogeochemical and physical land-atmosphere feedbacks, and interactions with human systems. A special focus of his research is the coupling of carbon, water and energy cycles with the biotic and abiotic cycling of nutrients such as nitrogen and phosphorus, which limit growth and metabolism of plants and microbes. He also studies the influence of disturbance on biogeochemistry-Earth system feedbacks, model evaluation and uncertainty quantification, and biometeorology.</p><p>“I am honored to be recognized as an AGU Fellow,” Thornton said. “The breadth of expertise representing biogeochemistry, atmospheric science, hydrology and global change research within the AGU community makes it a welcoming and stimulating intellectual home for understanding the Earth as a system of systems.&nbsp;</p><p>“I’m also grateful for the Education section, which has done so much to connect students of all ages with cutting-edge research opportunities. The collegiality and commitment to open science practiced by the AGU community sets an admirable standard for scientific organizations around the globe,” Thornton added.&nbsp;</p><p>Thornton is also a Fellow of the American Association for the Advancement of Science and has been recognized multiple times as a Highly Cited Researcher by Clarivate’s Web of Science. He was named an ORNL Corporate Fellow in 2023 for his achievements in terrestrial ecosystem modeling, mentoring of postdoctoral staff and students, and community engagement. He recently completed the Battelle Laboratory Operations Leadership Academy, which develops skills for managing large-scale collaborative science programs and institutions.&nbsp;</p><p>In addition to his research accomplishments, Thornton has served as mentor to several technology projects at Oak Ridge Schools, including as a FIRST Robotics mentor and as lead technical mentor for the student-led NASA CubeSat Launch Initiative. He is also a board member of the Oak Ridge Public Schools Education Foundation.</p><p>Thornton earned a doctorate in forestry from the University of Montana, a master’s degree in geography and environmental engineering from Johns Hopkins University, and a bachelor’s degree in biomedical engineering from Johns Hopkins.&nbsp;</p><p>UT-Battelle manages ORNL for the Department of Energy’s Office of Science, the single largest supporter of basic research in the physical sciences in the United States. The Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit&nbsp;<a href="https://www.energy.gov/science/office-science">energy.gov/science</a>.&nbsp; <em>—Stephanie Seay</em></p>
</description>
<link>https://www.ornl.gov/news/thornton-named-fellow-american-geophysical-union</link>
<guid isPermaLink="false">https://www.ornl.gov/news/thornton-named-fellow-american-geophysical-union</guid>
<pubDate>Wed, 24 Sep 2025 12:00:00 GMT</pubDate>
<author>Peter E Thornton</author>
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<title>Scientists visualize atomic structures in moiré materials</title>
<description><figure><img alt="On the left is an artistic depiction of a twisted double layer forming a moiré pattern created by overlapping 2D sheets; each layer’s structure is shown separately on the right. " width="1024" height="667" src="https://www.ornl.gov/sites/default/files/styles/large/public/2025-09/Harris-Xiao-illustration.jpg?itok=5_4S7Ydj" referrerpolicy="no-referrer"></figure>
<p>Researchers with the Department of Energy’s Oak Ridge National Laboratory and the University of Tennessee, Knoxville, have created an innovative method to visualize and analyze atomic structures within specially designed, ultrathin bilayer 2D materials. When precisely aligned at an angle, these materials exhibit unique properties that could lead to advancements in quantum computing, superconductors and ultraefficient electronics.</p><p>These developments bolster U.S. leadership in materials innovation, energy technologies and secure communication, and they lay the groundwork for a future defined by leading-edge progress.</p><h2><strong>Visualizing atoms in moiré materials</strong></h2><p>Layering the 2D materials at a slight angle creates intricate moiré patterns, similar to the wavy distortion seen when two window screens overlap.&nbsp;While visually striking, the patterns complicate efforts to identify individual atoms, even with advanced imaging tools such as&nbsp;scanning transmission electron microscopy (STEM). But knowing the locations of individual atoms is a crucial step for controlling defects or fine-tuning the material’s characteristics through techniques such as doping, where small amounts of other elements are added. The team’s findings challenge existing theories about atomic behavior in these complex materials.</p><p>“Theoretical models suggested that the substitutional site of a dopant atom in the material depended on its position within the moiré pattern. It has been very difficult or impossible to test those models with existing analysis tools. However, we devised a neural network trained to identify the location and layer of the dopant atoms in relation to the moiré pattern and conducted a detailed statistical analysis, which ultimately disproved that theory for our material synthesis technique. We were surprised to discover that the position of the atoms in the moiré pattern had no impact on the ease of atom substitution,” said Sumner Harris, an R&amp;D staff scientist at the Center for Nanophase Materials Sciences at ORNL and co-author of the study. The machine learning model the team developed is called Gomb-Net, short for groupwise combinatorial network.</p><h2><strong>Machine learning uncovers atomic patterns</strong></h2><p>“Gomb-Net enables us to separate the layers, overcoming the limitations of traditional analysis methods," Harris said. “Using the model, we deepened our understanding of how atoms are arranged within these complex structures, setting the stage for future research into understanding the unique properties of twisted 2D materials.”&nbsp;</p><p>Gomb-Net can be used on today’s personal computers, democratizing access to advanced analysis of moiré materials and is perfect for real-time deployment on electron microscopes for autonomous exploration of materials.</p><p>For the study’s experiment, the researchers added selenium, a nonmetal element that can tune a material’s electronic and optical behavior, to a twisted stack of two tungsten disulfide monolayers. These ultrathin layers, composed of tungsten and sulfur atoms just a few atoms thick, behave differently than the bulk material.&nbsp;</p><p>“By selectively replacing sulfur atoms in the stack with selenium, we aimed to investigate how the selenium was distributed within the intricate moiré patterns formed by the overlapping layers,” said Kai Xiao, a distinguished ORNL staff scientist in the Functional Hybrid Nanomaterials Group at CNMS, and co-author of the study.</p><p>The UT researchers used advanced STEM to visualize individual atoms in the twisted tungsten disulfide bilayer stack. This visualization provides vital information about the exact positions of the atoms and any possible defects that occurred during the material’s creation.</p><h2><strong>Implications for future technologies</strong></h2><p>Replacing sulfur with selenium can tune the electronic properties and adjust the band gap — the energy needed for electron motion, which is critical for semiconductors — while enhancing optical properties, or how the material interacts with light. This knowledge is essential for advancing technologies such as lasers and LED lights, making them more efficient and effective. Additionally, this tailored approach helps reduce defects, leading to more reliable and innovative technologies such as quantum computers.</p><p>This advancement extends beyond a specific material system, opening opportunities for all moiré materials. “We have talked to other microscopists studying moiré materials across the country, and in every conversation, they have an idea for how this analysis can be used for a system they are studying,” said Austin Houston, lead author and a doctoral student at UT. “This is really encouraging because it means we are working on something useful that has real potential to impact research across this field.”</p><p>Along with Houston, partners in the study from UT were Hao Wang, David Geohegan and Gerd Duscher. Yu-Chuan Lin of National Yang Ming Chiao Tung University in Taiwan also assisted the investigation.</p><p>The research paper,&nbsp;<a href="https://pubs.acs.org/doi/10.1021/acs.nanolett.5c01460">published in the journal <em>Nano Letters</em></a><em>,</em> provides details about the innovative method for visualizing atomic structures in 2D materials.&nbsp;</p><p>The DOE Basic Energy Sciences program funded this research. This work was supported by the DOE Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division. The materials synthesis experiments and machine learning development were performed at CNMS, a DOE Office of Science user facility at ORNL.</p><p>UT-Battelle manages ORNL for DOE’s Office of Science. The single largest supporter of basic research in the physical sciences in the United States, the Office of Science is working to address some of the most pressing challenges of our time. For more information, visit&nbsp;<a href="https://www.energy.gov/science"><strong>energy.gov/science</strong></a>.&nbsp;<em>—&nbsp;Scott Gibson</em>&nbsp;</p>
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<link>https://www.ornl.gov/news/scientists-visualize-atomic-structures-moire-materials</link>
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<pubDate>Tue, 23 Sep 2025 12:00:00 GMT</pubDate>
<author>Sumner Harris, Kai Xiao</author>
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