Nanoscale under gigapressure

2025/10/292025/10/30

Research team led by DESY and MAX IV scientists adapts important X-ray analysis method for use with difficult-to-move samples

Sometimes a change of perspective can make a world of difference. A team of scientists from DESY and MAX IV as well as University of Bayreuth has rearranged the method in which one can use an X-ray beam to image a sample without using high-quality lenses. The method, called ptychography, has been widely used at synchrotrons and free-electron lasers to analyse the inner workings of materials quickly enough while avoiding major damage to the sample by the X-rays. The team has turned the standard method of ptychography on its head: Instead of moving the sample around the X-ray beam, they have figured out how to move the X-ray beam itself in a way that does not alter the properties of the X-rays while still accomplishing the effect of ptychographic analysis. Moreover, they have tested the method on a sample that is in and of itself difficult to move – short-lived states of matter under extreme conditions of pressure and temperature. The team has published their findings in the Proceedings of the U.S. National Academy of Sciences (PNAS).

X-ray ptychography has become, in recent years, a standard technique in the toolbox of researchers using X-ray light sources. In a wide variety of fields, including biology and geology, the technique has been critical for imaging the interiors of samples up to atomic-scale detail non-destructively, revealing details on a scale that methods of light and electron microscopy cannot reach. Up to now, ptychography has been accomplished by using extremely precise sample movers that would change the position of the sample relative to the X-ray beam by tiny lengths – sometimes to the nanometre level – creating a grid pattern of sequentially imaged spots that eventually revealed the full image. Called high-resolution phase-contrast imaging, it has provided insights into the nanoscale structures of tiny biological structures, mineral deposits, computer chips and much more.

Read more on the DESY website

Image: Two views of an extreme-states experiment: To the left is an X-ray micrograph of the sample set up, which consisted of a piece of elemental iron surrounded by solid oxygen, itself surrounded by a rhenium gasket within a diamond anvil cell creating intense pressure. To the right is a ptychographic reconstruction of the area of the sample hit by X-rays, shown with a green circle. In that area using their new ptychographic method, the team could reconstruct the oxidation of the iron being melted by the intense pressure. An extreme-states experiment of this kind has not before been imaged in this way.

Credit: Tang Li, DESY

What will it take to bring fusion energy to the US power grid?

2025/05/072025/05/12

In this Q&A, Arianna Gleason discusses the technologies needed to make commercialized fusion energy a reality and how SLAC is advancing this energy frontier.

By Erin Woodward

Arianna Gleason is an award-winning scientist at the Department of Energy’s SLAC National Accelerator Laboratory who studies matter in its most extreme forms – from roiling magma in the center of our planet to the conditions inside the heart of distant stars. During Fusion Energy Week, we caught up with Gleason about the current state of fusion energy research and how SLAC is helping push the field forward.

What is fusion energy?

Fusion is at the heart of every star. The tremendous pressure and temperature at the center of a star fuses atoms together, creating many of the elements you see on the periodic table and generating an immense amount of energy. Fusion is exciting, because it could provide unlimited energy to our power grid. We’re trying to replicate fusion energy here on Earth, though it’s a tremendous challenge of science and engineering.

Have we ever been able to replicate fusion in a lab?

Fusion has been at the forefront of scientific inquiry for many decades, but it wasn’t until December 2022 that we reached an incredible watershed moment in fusion research. Using a technique called inertial fusion energy, or IFE, researchers at Lawrence Livermore National Laboratory’s National Ignition Facility (NIF) focused 192 individual lasers on a fuel “target” – about the size of a pea – made of deuterium and tritium. These lasers applied a tremendous force onto the target, and it imploded into a burning plasma. The deuterium and tritium atoms fused together, generating helium and a neutron and producing more energy from the reaction than was used to create it. For less than a trillionth of a second, researchers created the center of a star on Earth. After more than 50 years of fusion research, the world finally achieved net energy gain.

That’s incredible, but – a trillionth of a second? That seems pretty short.

Very short! The idea is that this process – this burning plasma – can be repeated many times per second, driven by a series of laser shots that create a source of power. Think of it like a car engine: A spark (the laser) ignites the fuel (the fusion fuel target), which only burns for a short time, but repeated cycles of ignition and burning drive sustained power. In the case of inertial fusion energy, this would be the equivalent of a one million horsepower engine.

Right now, the NIF produces one or two shots each day. We’re trying to go from one shot each day to multiple shots each second. If we can orchestrate these implosions multiple times a second, we can generate a continuous flow of power – and do so in a way that is safe, carbon-free and at a scale that meets the long-term energy demands of our world.

Now that we know fusion is possible on Earth, how far are we from having this unlimited energy source on our national power grid?

There are numerous barriers we need to overcome before commercialized fusion energy is a reality. As I said before, we need to move from one laser shot each day to something on the order of 10 shots per second. High repetition rate is critical. Beyond that, we need to develop the technology to deliver the fuel targets into the fusion chamber, track their movements and engage them with lasers at the same rate – 10 times per second. The third challenge is designing the targets themselves to ensure they fuse and generate energy every single time. Right now, our understanding of the physics and materials science of these targets is at an early stage – a very low technology readiness level.

Even more foundationally, we need people. We need to be training up experts at every level – from power plant operators, technicians and electricians to PhDs in science and engineering. These are good jobs that can be domestically sourced. We need to be educating the workforce, at all levels, for power plant design and operation.

What is SLAC doing to address these challenges?

SLAC is furthering fusion energy science and technology in several ways, including in partnership with other national labs, universities and private companies.

One significant opportunity is the challenge of high repetition rates – moving from one laser shot per day to 10 shots every second. SLAC has years of experience on exactly this topic. We are home to the only domestic X-ray free electron laser, the Linac Coherent Light Source (LCLS), and its cutting-edge experimental end stations. We’re leveraging these facilities to build up the capabilities for high-repetition laser-target interactions.

High-Power Laser Facility probes iron at the Earth’s core conditions

2025/01/202025/01/21

probe

Scientists have captured unprecedented detail of how iron behaves under extreme conditions approaching those of the core – advancing our understanding of planetary dynamics. Published in Physical Review Letters, these are the first experimental results from the new High-Power Laser Facility (HPLF) at the ESRF.

At the heart of our planet, Earth’s core comprises two distinct sections: a molten outer core that begins around 2,900 km beneath our feet, and a solid inner core starting around 5,150 km. Iron accounts for roughly 85% of the core by weight, combining with nickel and lighter elements to form alloys.

But uncertainties remain over the melting point of iron and its alloys under the extreme pressures of deep Earth. Debates also persist over how iron’s crystal structure may change with depth, which influences its physical and chemical properties at larger scales.

Shocked to the core

Fresh insights into these questions are revealed in new experimental work by Sofia Balugani, PhD student at the ESRF within the InnovaXN programme, in collaboration with the Ecole Polytechnique (LULI Laboratory, France), the First Light Fusion company (UK), and the HPLF team. The researchers “shocked” a tiny iron target (3.5 μm-thick) by firing it with a laser pulse, reaching a pressure of 240 GPa. By coupling the laser with X-rays, they recorded a bulk temperature measurement of 5,340K, the first of its kind for iron’s melting plateau under such extreme conditions. A melting point of 6200K was extrapolated for the even higher pressures of the inner core boundary (ICB).

“After three years of PhD research, this work fulfills my long-standing interest in planets, allowing me to study materials crucial to planets and their properties under extreme conditions, such as those on Earth,” says Balugani.

The research helps refine models of the Earth’s core’s behaviour. That’s because HPLF is optimised for this type of X-ray absorption experiment, which enabled the team to simultaneously track temperature alongside changes in the local order of iron. The findings rule out a transition in iron’s lattice structure to a high-temperature bcc (body-centred cubic) phase, which is observed in some other metals under shock compression such as copper and gold.

Instead, iron remains in the denser hcp (hexagonal close-packed) phase. The results may interest astrophysicists searching for exoplanets, given the importance of the core in generating a geomagnetic field and driving plate tectonics – both of which are key to supporting habitable conditions on Earth.

Read more on ESRF website

Image: The High-Power Laser Facility at the ESRF.

Credit: S. Candé.

Exploring Matter at or under Extreme Conditions at Diamond

2024/03/082024/03/12

We’re all familiar with ice – water frozen into its solid state, at or below 0°C at standard atmospheric pressure (1 atm, or 101.325 kPa). But this naturally occurring crystalline solid (officially known as ice Ih or ice one h) is just one of at least nineteen phases of ice, each with a different packing geometry. The less familiar phases (polymorphs) occur at different pressures and temperatures. The ice polymorphs have differing densities, crystalline structures, and proton ordering. These strange phases of ice are just one example of what happens to matter at extremely high pressures.

The physical and chemical properties of a material depend on its structure and the distances between its atoms. Pressure has far more of an effect on interatomic distances than temperature, so varying the pressure is a powerful tool for exploring the relationship between structure and properties. Fundamental insights can be used, for example, to inform the design of new materials or to help explain phenomena such as volcanic eruptions that originate from processes deep in the Earth.

Further, the electronic structure of a material can be very different under pressure, giving rise to extraordinary effects. An insulator such as ice can become a metal or conductor (e.g. Ice XVII, or Superionic water), and metals can become insulators. E.g. Sodium, a pale grey, shiny metal transforms into a glass-like transparent insulator under pressure. Changing electron configurations at high pressure gives elements a different reactivity and chemistry, almost reinventing the periodic table.

Annette Kleppe, Principal Beamline Scientist on Diamond’s I15 beamline, said;

High-pressure devices are superbly suitable for tuning structural and electronic properties of materials. In fact, pressure can change the electronic properties so dramatically that it adds a whole new dimension to the periodic table. High-pressure, when combined with different experimental analysis techniques, is a powerful tool for understanding natural phenomena or designing novel materials, for example. High-pressure research topics range from low-temperature physics to high-temperature Earth and planetary science.

It’s no wonder researchers want to explore these extreme conditions, and Diamond has several facilities to accommodate them. I15 is our dedicated Extreme Conditions beamline, dedicated to X-ray powder diffraction experiments at extreme pressures and temperatures. Users can also carry out high-pressure experiments on beamline I18 (Microfocus Spectroscopy), I19 (Small Molecule Single Crystal Diffraction), and I22 (Small Angle Scattering and Diffraction).

Dr Dominique Laniel from the University of Edinburgh said;

Single crystal X-ray diffraction studies of organic molecular solids – the basic building blocks of life – have mostly been confined to pressures below 10 GPa. It is hypothesised that beyond that pressure (equivalent to 100,000 bar), the void space in these solids approaches zero, a turning point in the behaviour of molecular structures. Zero void space meaning that further compression is expected to change the intramolecular and intermolecular bonding interactions . A multidisciplinary team from the Centre for Science at Extreme Conditions at the University of Edinburgh set out to test this theory and push the boundary for high-pressure investigations on this type of molecular solid using the simple amino acid glycine.

Lewis Clough is a joint PhD student between Diamond and the University of Edinburgh. He worked with colleagues from Edinburgh, studying the behaviour of the alpha polymorph of glycine, which persists to at least 50 GPa. Using high-pressure single-crystal diffraction on I15, the team achieved the highest single-crystal pressure data set collected at Diamond on an organic material.

For the experiment, a tiny 50 μm-sized single crystal of α-glycine was loaded into a diamond anvil cell (DAC), a pocket-sized high-pressure apparatus, in which the crystal was compressed between the tips of two diamonds. Using an X-ray energy of 78 keV – significantly higher than standard for single crystal diffraction experiments – the team collected very high-quality data and solved the structure to the highest pressures of 51-52 GPa.

Read more on Diamond website

Image: Photograph of a single crystal of α-glycine compressed to 52.76 GPa in a diamond anvil cell. A section of the crystal structure determined at this pressure is overlaid on the crystal, showing the layers that increase in proximity upon compression, revealing a network of inter-layer hydrogen bonding interactions.

A beautiful machine integrated within a peaceful forest setting

2023/11/092023/11/10

On World Science Day for Peace and Development, we’re heading to a forest in Switzerland!

Maël Clémence is a PhD student at the Swiss X-ray Free-Electron Laser (SwissFEL), which is located at the Paul Scherrer Institut (PSI) in Villigen, Switzerland. His #LightSourceSelfie journey starts in the forest on top of the facility where he explains that the SwissFEL was designed to be fully integrated with the natural environment. Maël then uses a popular mode of transport to travel to the facility entrance. He recalls his childhood fascination with light, what led him to fall in love with physics, and his path to the SwissFEL.

For his PhD studies, Maël is utilising the machine’s ultraintense, ultrashort X-ray pulses to study and investigate quantum properties of magnetic materials in extreme conditions. Being at the SwissFEL has enabled Maël to gain a deeper understanding of this beautiful machine and the huge amount of skill and dedication that is required by the teams responsible for building and maintaining it.

The word ‘teamwork’ best describes his job as, on good days and bad, everyone pulls together and supports each other.

You’ll discover one of Maël’s favourite free time activities at the close out of his #LightSourceSelfie. Happy viewing!

Find out more about the SwissFEL here

Researchers resolve decades-long debate about shock-compressed silicon with unprecedented detail

2022/10/132022/10/20

They saw how the material finds a path to contorting and flexing to avoid being irreversibly crushed.

BY ALI SUNDERMIER

Silicon, an element abundant in Earth’s crust, is currently the most widely used semiconductor material and is important in fields like engineering, geophysics and plasma physics. But despite decades of studies, how the material transforms when hit with powerful shockwaves has been a topic of longstanding debate.

“One might assume that because we have already studied silicon in so many ways there is nothing left to discover,” said Silvia Pandolfi, a researcher at the Department of Energy’s SLAC National Accelerator Laboratory. “But there are still some important aspects of its behavior that are not clear.”

Now, researchers at SLAC have finally put this controversy to rest, providing the first direct, high-fidelity view of how a single silicon crystal deforms during shock compression on nanosecond timescales. To do so, they studied the crystal with X-rays from SLAC’s Linac Coherent Light Source (LCLS) X-ray laser. The team published their results in Nature Communications on September 21^st. What they learned could lead to more accurate models that better predict what will happen to certain materials in extreme conditions.

“This is a great example of an experiment that’s necessary to better understand certain materials,” said SLAC scientist Arianna Gleason, who was the principal investigator. “You have to start simple, with single crystals, to know what you’re tracking and understand it in really detailed ways before you can build up complexity to give way to, say, the next semiconductor of the 21^st Century that will allow the electronics industry to continue the remarkable progress seen in the past 50 years.”

Read more on the SLAC website

Karen Appel’s #My1stLight

2022/06/122022/06/13

Karen was a beamline scientist at DESY and is currently a beamline scientist at the European XFEL

My first synchrotron experiment was at beamline L at DORIS at DESY, which at that time just set up the possibility to do micro-focus X-ray fluorescence measurements. The first experiment I was involved in was headed by the group of Prof Schenk at the Institute of Mineralogy of the University of Kiel and focused on minerals that were formed at high pressures and high temperatures. At that moment, I was a PhD student at the University of Bonn, working on metamorphic rocks and isotope geochemistry of rocks and got involved in the experiment, because I was interested in analytical methods that could be applied to minerals that were formed at high pressures and temperatures. Besides some connections through my earlier studies, my main interest was to learn about this new method of X-ray fluoresence. We investigated the chemical trace element composition (Rare Earth elements) of minerals that were formed during metamorphic processes and commonly show a gradient of the element distribution, which is related to the metamorphic formation process.

As we were simply providing the samples, we had the chance to have a close look at the instrumentation. Having worked with commercial machines so far, I remember that I was very much impressed by the modular set- up of a beamline and this one-day experience motivated me to apply for a job that was offered from GFZ Potsdam that included a main part in experimental work at beamline L.

Later, as a postdoc, my experiences led me into the van Gogh experiment, where we used the polychromatic mode at beamline L and were able to detect the elemental distributions of a van Gogh painting. Now I am working at the High Energy Density Science instrument at the European XFEL, studying extreme states of matter, allowing me to work as a beamline scientist and also pursue my own scientific interests.

Image (above): Karen and her colleague working at the experimental station at the beamline L of DORIS III.

Credit: DESY

**Image:** DE: Die Experimentierstation HED (High Energy Density Science) dient der Erforschung von Materie unter extremen Druck- und Temperaturbedingungen oder sehr starken elektromagnetischen Feldern. Zu den wissenschaftlichen Anwendungen gehört die Untersuchung von Zuständen, wie sie im Inneren astrophysikalischer Objekte wie Exoplaneten bestehen, von Phasenzuständen unter extremem Druck, von Plasmen mit hoher Dichte oder von Phasenübergängen komplexer Feststoffe unter dem Einfluss starker Magnetfelder. EN: The HED experiment station will be used to study matter under extreme conditions of pressure, temperature, or electromagnetic fields. Scientific applications will be studies of matter occurring inside astrophysical objects such as exoplanets, of new extreme-pressure phases and solid-density plasmas, and of phase transitions of complex solids in high magnetic fields.

Credit: European XFEL / Jan Hosan

High-pressure experiments provide insight into icy planets

2021/03/122021/03/16

Research team determines compression behaviour of water ice in unprecedented detail

An international team of scientists has been using X-rays to take a look inside distant ice planets. At the PETRA III Extreme Conditions Beamline, they investigated how water ice behaves at high pressure, under conditions corresponding to those inside the planet Neptune, for example. At pressures up to almost two million times atmospheric pressure at sea level on Earth, the researchers were able to observe in unparalleled detail how water ice behaves under compression. The team, led by Hauke Marquardt from the University of Oxford, is presenting its findings in the scientific journal Physical Review B.

Planetary ices – such as water ice (H₂O), methane ice (CH₄) and ammonia ice (NH₃) – make up large parts of the ice giants in our solar system and are very likely to occur inside many exoplanets, which are planets outside our solar system. “However, the physical properties and phase diagrams of these compounds are not sufficiently known at the pressures and temperatures that prevail inside planets,” explains Marquardt. “Previous experimental studies using X-ray diffraction in a static diamond anvil cell have contributed a great deal to our understanding of ices at high pressure, but they have been unable to adequately answer numerous questions.”