Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New magnetism research brings high-temp superconductivity applications closer

11.04.2016

A research team led by the U.S. Department of Energy's (DOE) Argonne National Laboratory has discovered that only half the atoms in some iron-based superconductors are magnetic, providing a conclusive demonstration of the wave-like properties of metallic magnetism in these materials.

The discovery allows for a clearer understanding of the magnetism in some compounds of iron, the iron arsenides, and how it helps induce superconductivity, the resistance-free flow of electrical current through a solid-state material, which occurs at temperatures up to 138 degrees Kelvin, or minus -135 degrees Celsius.


Magnetic order in (Sr,Na)Fe2As2: The crystal structure contains planes of iron atoms (shown as red spheres). Half the iron sites have a magnetization (shown as red arrows), which points either up or down, but the other half have zero magnetization. This shows that the magnetism results from the constructive and destructive interference of two magnetization waves, a clear sign that the magnetic electrons are itinerant, which means they are not confined to a single site. The same electrons are responsible for the superconductivity at lower temperature.

Credit: Osborn et. al

"In order to be able to design novel superconducting materials, one must understand what causes superconductivity," said Argonne senior physicist Raymond Osborn, one of the project's lead researchers.

"Understanding the origin of magnetism is a first vital step towards obtaining an understanding of what makes these materials superconducting. Given the similarity to other materials, such as the copper-based superconductors, our goal was to improve our understanding of high-temperature superconductivity."

From an applied perspective, such an understanding would allow for the development of magnetic energy-storage systems, fast-charging batteries for electric cars and a highly efficient electrical grid, said Argonne senior physicist Stephan Rosenkranz, the project's other lead researcher.

Superconductors reduce power loss. The use of high-temperature superconducting materials in the electrical grid, for example, would significantly reduce the large amount of electricity that is lost as it travels though the grid, enabling the grid to operate more efficiently.

The researchers were able to show that the magnetism in these materials was produced by mobile electrons that are not bound to a particular iron atom, producing waves of magnetization throughout the sample. They discovered that, in some iron arsenides, two waves interfere to cancel out, producing zero magnetization in some atoms. This quantum interference, which has never been seen before, was revealed by Mössbauer spectroscopy, which is extremely sensitive to the magnetism on each iron site.

Researchers also used high-resolution X-ray diffraction at the Advanced Photon Source (APS) and neutron diffraction at Oak Ridge National Laboratory's Spallation Neutron Source (SNS) to determine the chemical and magnetic structures and to map the electronic phase diagram of the samples used. The APS and SNS are DOE Office of Science User Facilities.

"By combining neutron diffraction and Mössbauer spectroscopy, we were able to establish unambiguously that this novel magnetic ground state has a non-uniform magnetization that can only be produced by itinerant electrons. These same electrons are responsible for the superconductivity," Rosenkranz said.

The research is available in the January 25, 2016 online edition of Nature Physics.

Next, Rosenkranz and Osborn plan to characterize the magnetic excitations, or fluctuations of iron-based superconductors, to determine how they to relate to and possibly cause superconductivity.

###

The research team also included J.M. Allred, D.E. Bugaris, D.Y. Chung, H. Claus and S.H. Lapidus of Argonne; K.M. Taddei, M.J. Krogstad and O. Chmaissem of Argonne and Northern Illinois University; M.G. Kanatzidis of Argonne and Northwestern University; D.E. Brown of Northern Illinois University; J. Kang, R.M. Fernandes of the University of Minnesota; and I. Eremin of Ruhr-Universtat Bochum in German and the National University of Science and Technology in Moscow.

This work was supported by the DOE Office of Science.

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation's first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America's scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy's Office of Science. The U.S. Department of Energy's Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit the Office of Science website.

Media Contact

Jared Sagoff
jsagoff@anl.gov
630-252-5549

 @argonne

http://www.anl.gov 

Jared Sagoff | EurekAlert!

More articles from Physics and Astronomy:

nachricht X-ray photoelectron spectroscopy under real ambient pressure conditions
28.06.2017 | National Institutes of Natural Sciences

nachricht New photoacoustic technique detects gases at parts-per-quadrillion level
28.06.2017 | Brown University

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Supersensitive through quantum entanglement

28.06.2017 | Physics and Astronomy

X-ray photoelectron spectroscopy under real ambient pressure conditions

28.06.2017 | Physics and Astronomy

Mice provide insight into genetics of autism spectrum disorders

28.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>