International Day of Light #LightSourceSelfie special from the SLS

A community driven by curiosity!

To celebrate International Day of Light 2023, we bring you a #LightSourceSelfies special (see below) from Ludmila Leroy, a postdoc at the Swiss Light Source (SLS), which is located at the Paul Scherrer Institut (PSI) in Villigen, Switzerland. With an energy of 2.4 GeV, the SLS provides photon beams of high brightness for research in materials science, biology and chemistry.

Ludmila, who is from Brazil, is studying the properties of magnetic materials. She highlights the versatility of light sources as hugely advantageous to science and learning from, and about, nature. “We are all driven by curiosity and these versatile facilities gives us the ability to try different approaches and push the boundaries in our experiments.” Looking back on her career to date, Ludmila would advise her younger self “not to be scared to reach out for the world” as there are many light sources facilities around the globe and travelling to different countries is an exciting part of being a scientist.

As with all light sources, the SLS operates around the clock and Ludmila has a new take on making night shifts more bearable. Throughout the #LightSourceSelfie campaign, most participants have mentioned coffee, chocolate or candy when talking about night shift survival strategies. For Ludmila, night shifts are more bearable when she eats healthily and makes sure that she keeps hydrated.

And when she is not at a light source….Ludmila is in charge of the Music Club at PSI, which brings together a mixture of PhD students, postdocs, technicians and staff scientists. The PSIchedelics is just one of the society’s musical entertainment offerings. Ludmila plays the bass and sings in this band and her #LightSourceSelfie ends with a fantastic clip of them in action. You can find out more about music at PSI here: Music at PSI | Our Research | Paul Scherrer Institut (PSI)

Laura Heyderman elected Royal Society Fellow

Today, the announcement was made that Laura Heyderman, who leads the Mesoscopic Systems Group at PSI, has been elected Fellow of the Royal Society (FRS). Laura’s nomination recognises almost 30 years of research into magnetic materials and magnetism on the nanoscale, most notably, in the field of artificial spin ice.

Laura Heyderman is best known for her breakthroughs with nanomagnets – minute bar magnets that are a few hundreds of times smaller than the width of a human hair. Her research group, shared between Paul Scherrer Institute PSI and ETH Zurich where she became full professor in 2013, use these to create elaborate structures and devices. With the help of the large research infrastructures at PSI (X-rays, muons and neutrons) they then investigate the novel phenomena that they exhibit. The tiny magnetic systems they create can have a range of technological applications, such as for computation, communication, sensors or actuators.

Read more on the PSI website

Image: Laura Heyderman began working on magnetism as a PhD student investigating magnetic thin films in Paris in 1988. Today, she leads the Mesoscopic Systems Group, shared between PSI and ETH where she is a full professor.

Credit: ETH Zurich / Giulia Marthaler

Spintronics: A new tool at BESSY II for chirality investigations

Information on complex magnetic structures is crucial to understand and develop spintronic materials. Now, a new instrument named ALICE II is available at BESSY II. It allows magnetic X-ray scattering in reciprocal space using a new large area detector. A team at HZB and Technical University Munich has demonstrated the performance of ALICE II by analysing helical and conical magnetic states of an archetypal single crystal skyrmion host. ALICE II is now available for guest users at BESSY II.

The new instrument was conceived and constructed by HZB physicist Dr. Florin Radu and the technical design department at HZB in close cooperation with Prof. Christian Back from the Technical University Munich and his technical support. It is now available for guest users at BESSY II as well.

“ALICE II has an unique capability, namely to allow for magnetic X-ray scattering in reciprocal space using a new large area detector, and this at up to the highest allowed reflected angles”, Radu explains. To demonstrate the performance of the new instrument, the scientists examined a polished sample of Cu2OSeO3.

Read more on the HZB website

Image: The picture reflects the main effect measured with a newly developed instrument ALICE II at BESSY II: A circular polarised soft-X-ray beam scatters off a crystal that exhibits a helical or conical magnetic order. This leads to two scattered beams of different intensity. The difference in intensity of these scattered beams is a measure of the chirality of the equidistant magnetic helices.

Credit: © F. Radu/HZB

World changing science with precious photons

he 3.4 km long European XFEL generates extremely intense X-ray flashes used by researchers from all over the world. The flashes are produced in underground tunnels and they enable scientists to conduct a wide range of experiments including mapping atomic details of viruses, filming chemical reactions, and studying processes in the interior of planets.

Michael Schneider is a physicist at the Max Born Institute in Berlin. He uses synchrotrons and free electron lasers, such as the European XFEL, to study magnetism and magnetic materials. Michael’s fascinating #LightSourceSelfie takes you inside the European XFEL where he recalls the fact that it was large scale facilities themselves that first attracted him to his area of fundamental research. The work is bringing us closer to a new generation of computing devices that work more like the neurons in our brains that the transistors that we currently have in our computers. Michael captures the dedication of his colleagues and the facility teams, along with the type of work that you can get involved with at large scale facilities. He also gives a brilliant overview of the stages involved in conducting research at a light source. Michael is clearly very passionate about his science, but also finds time for some great hobbies too!

New 12 T magnet strengthens energy and magnetism research

Electron paramagnetic resonance (THz-EPR) at BESSY II provides important information on the electronic structure of novel magnetic materials and catalysts. In mid-January 2022, the researchers brought a new, superconducting 12-T magnet into operation at this end station, which promises new scientific insights.

At the THz-EPR end station, unique experimental conditions are provided through a combination of coherent THz-light from BESSY II and high magnetic fields. These capabilities have now been extended by a new superconducting 12 T magnet, acquired through funding from the BMBF network project “ERP-on-a-Chip” and HZB.

Read more on the HZB website

Image: Exhausted but happy: f.l.t.r. – K. Holldack (HZB), A. Schnegg (MPI CEC Mülheim, HZB), T. Lohmiller (HZB, HUB), D. Ponwitz (HZB) after the successful commissioning of the new 12T magnet (green).

Probing the Structure of a Promising NASICON Material

As physicists, materials scientists, and engineers continue striving to enhance and improve batteries and other energy storage technologies, a key focus is on finding or designing new ways to make electrodes and electrolytes.  One promising avenue of research involves solid-state materials, making possible batteries free of liquid electrolytes, which can pose fire and corrosion hazards.  An international group of researchers joined with scientists at Argonne National Laboratory to investigate the structure of crystalline and amorphous compounds based on the NASICON system, or sodium super-ion conductors. The work (using research carried out at the U.S. Department of Energy’s Advanced Photon Source [APS] and published in the Journal of Chemical Physics) reveals some substantial differences between the crystalline and glass phases of the NAGP system, which affect the ionic conductivity of the various materials.  The investigators note that the fraction of non-bridging oxygen (NBO) atoms appears to play a significant role, possibly altering the Na+ ion mobility, and suggest this as an area of further study.  The work provides fresh insights into the process of homogeneous nucleation and identifying superstructural units in glass ― a necessary step in engineering effective solid-state electrolytes with enhanced ionic conductivity. 

Because of their high ionic conductivity, materials with a NASICON structure are prime candidates for a solid electrolyte in sodium-ion batteries.  They can be prepared by a glass-ceramic route, which involves the crystallization of a precursor glass, giving them the usefulness of moldable bulk materials.  In this work, the research team specifically studied the NAGP system [Na1+xAlxGe2-x(PO4)3] with x = 0, 0.4 and 0.8 in both crystalline and glassy forms. Working at several different facilities, they used a combination of techniques, including neutron and x-ray diffraction, along with 27Al and 31P magic angle spinning and 31P/23Na double-resonance nuclear magnetic resonance spectroscopy.  The glassy form of NAGP materials was examined both in its as-prepared state and after thermal annealing, so that the changes on crystal nucleation could be studied.

Neutron powder diffraction measurements were performed at the BER II reactor source, Helmholtz-Zentrum Berlin, using the fine resolution powder diffractometer E9 (FIREPOD), followed by Rietveld analysis.  Further neutron diffraction observations were conducted at the Institut Laue-Langevin using the D4c diffractometer and at the ISIS pulsed neutron source using the GEM diffractometer.  X-ray diffraction studies were performed at X-ray Science Division Magnetic Materials Group’s beamline 6-ID-D of the APS, an Office of Science user facility at Argonne National Laboratory. 

Read more on the APS website

Image: Fig. 1. NASICON crystal structure showing the tetrahedral P(4) phosphate motifs (purple), octahedral GeO6 motifs (cyan) and Na+ ions (green). Oxygen atoms are depicted in red.