electronic structure – Lightsources.org

Revealing the Electronic Signature of Unusual Magnetism

2026/06/092026/06/18

SCIENTIFIC ACHIEVEMENT

Experiments at the Advanced Light Source (ALS) showed how magnetic Co atoms sandwiched between TaS₂ layers reshape the material’s electronic structure.

SIGNIFICANCE AND IMPACT

Understanding how unusual magnetic order influences electron movements in new quantum materials like CoxTaS₂ could guide their use in advanced quantum technologies.

Tracing the electronic fingerprints of exotic magnetism

Van der Waals magnets that have layered structures offer a unique platform for exploring novel quantum states and their underlying physics. To discover how to harness their properties for use in next-generation electronics and data storage technologies, researchers are working to identify the electronic fingerprints of the exotic magnetic features in systems such as CoxTaS₂.

CoxTaS₂ belongs to a class of van der Waals magnets called magnetically intercalated transition metal dichalcogenides (TMDs). In these structures, magnetic atoms (cobalt, Co) are inserted between layers of a two-dimensional semiconductor (2H-TaS₂). At extremely low temperatures, the cobalt atoms develop a very unusual non-coplanar magnetic order which researchers believe is responsible for the material’s exotic properties. In particular, they suspect that the unusual magnetism strongly influences how electrons move.

In this study, a group of researchers led by UC Berkeley, in collaboration with ALS scientists, aimed to reveal spectroscopic evidence of how magnetic order changes the behavior of itinerant electrons in CoxTaS₂.

The relationship between the structure of polyurethane frameworks and the structural and superconducting properties of Y-123 foams

2024/04/162024/04/24

A Polish team of researchers led by Dr. Paweł Pęczkowski from the Institute of Physical Sciences, Faculty of Mathematics and Natural Sciences, Cardinal Stefan Wyszyński University used the PIRX beam to study the properties of the electronic structure of superconducting foams obtained on the basis of polyurethane foams. The research results were published in the Journal of the European Ceramic Society published by Elsevier.

High-temperature superconductors (HTS) are most often produced in one of three varieties – thin film, wire (tape) and loose. This division results from the properties of these superconductors, which originate from their microstructure. High-temperature superconductors can be produced in a fourth variant with a foam structure. Superconductors with a foam structure have a much shorter cooling time, so the transition or return to the superconducting state from the normal state is much faster than in the case of solid samples manufactured using the top-seeded infiltration-growth (TSIG) method. Additionally, they are lightweight and exhibit fewer micro-cracks, which are the main factor limiting the critical current density in solid superconducting samples. These unique features make superconducting foams an excellent material for space applications, where it is necessary to use strong and light sources of magnetic fields to build, for example, docking mechanisms for space vehicles and ion engines. However, before superconducting foams are used, several basic questions need to be answered: what is the impact of changes in the foam structure (e.g. size and shape of pores) on superconducting properties, how does current flow in the three-dimensional structure of the foam and what is its impact on the properties related to ability to anchor vortexes (pinning centers).

Read more on SOLARIS website

Image: (a) Y-211 foam before and (b) after Y-035 infiltration process; (c) Y-123 – final foam levitation in a magnetic field

X-ray Excited Optical Luminescence (XEOL)

2023/10/232023/10/31

XEOL is an X-ray photon in/optical photon out technique that is related to the conversion of the X-ray energy absorbed by the materials to optical photons, involving multi-step energy transfer cascade processes. XEOL is often used together with XANES to reveal the electronic structure and optical properties of the system of interest, such as rare earth down conversion phosphors, quantum confined semiconductors, heterogeneous materials etc., and is applied in display/lighting technologies (TV, smartphone and LED lamps), scintillators, rechargeable batteries and energy conversion devices (photovoltaic cells). XEOL is now available at the end station of BM-08 XAFS/XRF beamline with emission spectra measurement capability under irradiation with X-ray beam.

Read more in SESAME website

Image: General view of the XEOL experimental setup at BM-08 XAFS/XRF beamline. Sample environment with optical fiber for collecting the luminescence signals

Life in synchrotron radiation research

2021/12/012021/12/02

Including the day an earthquake interrupted my beam time!

Today’s #LightSourceSelfie is brought to you by Ro-Ya Liu, Assistant Research Scientist at NSRRC, operators of the Taiwan Light Source and the Taiwan Photon Source. Ro-Ya’s research area is focused on probing the electronic structure of novel materials by using angle resolved photoemission spectroscopy. She was inspired by her Master’s supervisor whose eyes shone as he presented his new data on the quantum well state of ultra-high silver thin film. Ro-Ya wanted to experience this spark and purpose in life. After a shaky first experiment (literally shaky due to an Earthquake!), Ro-Ya has done just that during a career that has already involved working at the Taiwan Light Source, the Photon Factory, Spring 8, HiSOR, Elettra, the Advanced Light Source and Diamond Light Source. Ro-Ya is still learning from colleagues including beamline engineers and users coming to conduct experiments at the Taiwan Light Source. Their deep knowledge helps Ro-Ya in her beamline manager role. She is looking to dig deep to acquire this knowledge and continue to find great purpose in her life in synchrotron radiation research.