Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ames Laboratory scientists discover new family of quasicrystals

11.06.2013
Scientists at the U.S. Department of Energy’s (DOE) Ames Laboratory have discovered a new family of rare-earth quasicrystals using an algorithm they developed to help pinpoint them.
Quasicrystalline materials may be found close to crystalline phases that contain similar atomic motifs, called crystalline approximants. And just like fishing experts know that casting a line in the right habitat hooks the big catch, the scientists used their knowledge to hone in on just the right spot for new quasicrystal materials discovery.

Their research resulted in finding the only known magnetic rare earth icosahedral binary quasicrystals, now providing a “matched set” of magnetic quasicrystals and their closely related periodic cousins.

The discovery has been published online by the journal Nature Materials in an article, “A family of binary magnetic icosahedral quasicrystals based on rare earth and cadmium.”
“This discovery of binary magnetic quasicrystals provides us with a means of doing a cleaner comparison of structural and magnetic properties between a quasicrystal and its periodic approximant,” said Alan Goldman, Ames Laboratory faculty scientist and a distinguished professor at Iowa State University. “It’s a tremendously exciting thing.”

Goldman is part of the Ames Laboratory’s research group which studies the microscopic properties of crystals through neutron and x-ray scattering performed at Argonne National Laboratory’s Advanced Photon Source. His collaborator, Ames Laboratory faculty scientist and Iowa State University distinguished professor Paul Canfield, was one of the first scientists able to grow single-grain, rare-earth quasicrystals, and his work continues in discovering, growing, and characterizing them.

Since the 1982 discovery of quasicrystals-- intermetallic compounds that are ordered but not periodic--by Nobel Prize winning chemist Dan Shechtman, many have been synthesized by researchers worldwide, and one has even been discovered occurring naturally.

But scientists at the Ames Laboratory, with their expertise in rare earths and magnetism, were beginning to look for the next step after that revolutionary first discovery.

“For the last ten years, we have been moving beyond just the innate beauty of these quasicrystalline structures to find out what else is interesting about them. Are the electrical properties any different? Are the magnetic qualities unusual?” Goldman asked.

Goldman and Canfield, like many researchers around the world began to wonder what magnetic properties would do, extended to the unique design of quasicrystals.

“If you could place magnetism on these quasicrystal structures, what would it look like?” Canfield said the researchers wondered. “You can have antiferromagnets or ferromagnets in the crystalline or periodic example. You have a disordered magnet or spin glass with the amorphous system. This is known. But with quasicrystals, you have an aperiodic arrangement. Will it affect the magnetism in some weird or novel way? It’s a strange environment for magnetism.”

“There’s been a lot of theoretical and experimental work on magnetic quasicrystals and mathematically there’s no reason why magnetic ordering can’t happen,” said Goldman. “But experimentally it was never observed. Why? What does this teach us about magnetism in complex environments?”

A few years ago, a series of periodic approximants of rare-earth cadmium were discovered that did order magnetically by research colleagues in Japan. The Ames Laboratory scientists worked to characterize by scattering the magnetic structures in collaboration with other researchers from France, Japan, and the United States.

Goldman and Canfield suspected that there could be quasicrystals very close to these rare earth cadmium approximants, hidden in very limited regions of temperature and composition space in the phase diagram, and most easily attainable through the flux growth method Canfield has used to grow other quasicrystals. Together with Ames Lab scientists Sergey Bud’ko, Andreas Kreyssig, Kevin Dennis, Mehmet Ramazanoglu, Anton Jesche, and physics graduate student Tai Kong, Goldman and Canfield initiated a new search for magnetic quasicrystals.

Goldman asked Canfield to start by growing the approximant, but Canfield was shooting for both.

“My intent was not just to go to the approximant, but to cool this as far as I could before everything solidified; I was fishing for the binary quasicrystal,” Canfield said. “It was an attempt to survey the system. I know there’s an approximant in there, but is there another surprise?”

And sure enough, there was. Canfield had grown the approximant, but he also found the presence of faceted pentagonal dodecahedra, one of the signatures of quasicrystals. Goldman’s x-ray scattering work confirmed the material as a quasicrystal.

In the rare earth cadmium approximants, there is magnetic order. In the quasicrystalline materials, however, the scientists found spin glass behavior, similar to the magnetic behavior in amorphous materials.

“What we have here is proof of principle. Yes, you can find quasicrystals near approximants; you just have to search the right way,” said Canfield.

“There’s still work to be done; it’s my hope that there is lurking out there a quasicrystalline antiferromagnet, which means an ordered magnetic structure. It hasn’t been theoretically ruled out,” said Goldman. “What I do know is that quasicrystals continue to surprise me.”

The research was supported by DOE’s Office of Science.

The Ames Laboratory is a U.S. Department of Energy Office of Science national laboratory operated by Iowa State University. The Ames Laboratory creates innovative materials, technologies and energy solutions. We use our expertise, unique capabilities and interdisciplinary collaborations to solve global problems.

The Advanced Photon Source at Argonne National Laboratory is one of five national synchrotron radiation light sources supported by the U.S. Department of Energy’s Office of Science to carry out applied and basic research to understand, predict, and ultimately control matter and energy at the electronic, atomic, and molecular levels, provide the foundations for new energy technologies, and support DOE missions in energy, environment, and national security. To learn more about the DOE Office of Science X-ray user facilities, visit the DOE Office of Science website.

DOE’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, please visit science.energy.gov
Contacts:
Alan Goldman, Division of Materials Science and Engineering, (515) 294-3585
Paul Canfield, Division of Materials Science and Engineering, (515) 294-6270
Laura Millsaps, Public Affairs, (515) 294-3474

Laura Millsaps | EurekAlert!
Further information:
http://www.ameslab.gov
http://www.ameslab.gov/news/news-releases/ames-laboratory-scientists-discover-new-family-quasicrystals

More articles from Materials Sciences:

nachricht Spin current detection in quantum materials unlocks potential for alternative electronics
16.10.2017 | DOE/Oak Ridge National Laboratory

nachricht Missing atoms in a forgotten crystal bring luminescence
11.10.2017 | King Abdullah University of Science & Technology (KAUST)

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

Im Focus: New nanomaterial can extract hydrogen fuel from seawater

Hybrid material converts more sunlight and can weather seawater's harsh conditions

It's possible to produce hydrogen to power fuel cells by extracting the gas from seawater, but the electricity required to do it makes the process costly. UCF...

Im Focus: Small collisions make big impact on Mercury's thin atmosphere

Mercury, our smallest planetary neighbor, has very little to call an atmosphere, but it does have a strange weather pattern: morning micro-meteor showers.

Recent modeling along with previously published results from NASA's MESSENGER spacecraft -- short for Mercury Surface, Space Environment, Geochemistry and...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

Conference Week RRR2017 on Renewable Resources from Wet and Rewetted Peatlands

28.09.2017 | Event News

 
Latest News

A single photon reveals quantum entanglement of 16 million atoms

16.10.2017 | Physics and Astronomy

The melting ice makes the sea around Greenland less saline

16.10.2017 | Earth Sciences

On the generation of solar spicules and Alfvenic waves

16.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>