Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > New Evidence to Aid Search for Charge 'Stripes' in Superconductors: Findings identify signature that will help scientists investigate and understand materials that carry current with no resistance

Click on the image to download a high-resolution version. Searching for stripes: Scientists Simon Billinge, Milinda Abeykoon, Emil Bozin, and John Tranquada are making strides toward uncovering the role of "charge stripes" in superconductivity, the ability of some materials to carry electric current with no energy loss.
Click on the image to download a high-resolution version. Searching for stripes: Scientists Simon Billinge, Milinda Abeykoon, Emil Bozin, and John Tranquada are making strides toward uncovering the role of "charge stripes" in superconductivity, the ability of some materials to carry electric current with no energy loss.

Abstract:
Scientists at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory have identified a series of clues that particular arrangements of electrical charges known as "stripes" may play a role in superconductivity-the ability of some materials to carry electric current with no energy loss. But uncovering the detailed relationship between these stripe patterns and the appearance or disappearance of superconductivity is extremely difficult, particularly because the stripes that may accompany superconductivity are very likely moving, or fluctuating.

New Evidence to Aid Search for Charge 'Stripes' in Superconductors: Findings identify signature that will help scientists investigate and understand materials that carry current with no resistance

Upton, NY | Posted on September 3rd, 2013

As a step toward solving this problem, the Brookhaven team used an indirect method to detect fluctuating stripes of charge density in a material closely related to a superconductor. The research, described in a paper published online in Physical Review Letters August 30, 2013, identifies a key signature to look for in superconductors as scientists seek ways to better understand and engineer these materials for future energy-saving applications.

"In previous experiments, we've seen evidence of fluctuating "magnetic spin" stripes-patterns of how adjacent atoms' spin directions are arranged-that are compatible with superconductivity," said Brookhaven physicist John Tranquada, a senior collaborator on the research team. "Now we're trying to look at the arrangements of charge density, to see if there are alternating stripes of densely and more loosely packed charges. The charge part is harder to see."

To get an idea of the difficulty of tracking moving stripes, think of the cars in a supermarket parking lot. The lines delineating the parking spots are like the positions of atoms making up a crystal, and the cars are like the electrons. If there's a pattern to the arrangement-say alternating colors of cars in adjacent spots-it would be easy to spot in a single snapshot. But if you took a single photo (with a very long exposure) over the course of a busy shopping day as cars moved into and out of spots, all you'd see is a blur. You wouldn't be able to tell if they continued to park in alternating order, if the details of the parking pattern were changing, or even whether there was a pattern at all.

A series of individual snapshots might make the details more discernable. But in the case of analyzing materials science samples, the "snapshots" are often made with very intense x-rays or neutron beams. And access to beam time at these imaging facilities is limited, and expensive. "You can't throw enough 'light' on the problem to see it," Tranquada said.

Instead, the scientists tried a completely different approach. Rather than looking directly at the stripes they looked for a telltale signal that indicates the presence of the stripes by association, but in a different measurement that can be done quickly and with much less precious beam time. They started these experiments on a material they knew had a static striped pattern below a certain temperature to make sure that the signal was evident in this new measurement. They then studied what happened as the temperature rose to see whether the stripes would either disappear or persist but start to move.

The scientists ground up crystals of the test material into a fine powder and placed samples of it in line with a beam of neutrons at the Los Alamos Neutron Scattering Center at Los Alamos National Laboratory. Similar to the way light reflecting off an object enters your eyes to create an image, the neutron beams diffracted by the crystals' atoms yield information about the positions of the atoms. The scientists used that information to infer the material's electronic structure, and repeated the experiment at gradually warmer temperatures.

"We're looking at the average crystal structure, the height-to-width aspect ratio of that structure, and how different the positions of the atoms are from that average," said Milinda Abeykoon, lead author on the paper.

In the static striped arrangement, the atoms are displaced from the average in a regular way-like parking spots that are alternatingly wider or narrower than average. Such atomic displacements force the electrons to follow a stripe-ordered arrangement-the way smaller cars would fill the narrow parking spots alternating with wider SUVs.

With increasing temperature, the scientists found that while the aspect ratio of the crystal structure changed, the displacements from average structure persisted, leading them to conclude by inference that the striped pattern of charge density also remained, even though it was no longer static.

"This is the first powder diffraction scattering evidence for fluctuating charge stripes above the temperature where we see static order," said co-author Simon Billinge, referring to the new measurement. Billinge, who holds a joint appointment with Brookhaven Lab and Columbia University's School of Engineering and Applied Science, leads the collaboration that performed this study.

"One of the most critical aspects of this experiment is that we had lots of different data points, lots of temperatures-so you can catch small deviations," said co-author Emil Bozin of Brookhaven. He also noted how improvements in detector technology made it possible to collect a lot of data within a fixed amount of time. "Ten years ago we would have needed a couple of weeks of beam time to do this experiment; we collected all our data in just a few days."

The next step: Return to searching for stripes in superconductors. "This model system teaches us what diffraction-scattering signature to look for in copper-based superconductors to see if these fluctuations exist," Bozin said.

That search should lead to better understanding of the role of stripes in superconductivity, and possibly to new approaches to engineer advanced superconductors for energy applications.

Additional collaborators on this study are Wei-Guo Yin, Genda Gu, and John Hill of Brookhaven.

This research was funded by the DOE Office of Science.

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

####

About Brookhaven National Laboratory
One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. Brookhaven is operated and managed for DOE's Office of Science by Brookhaven Science Associates, a limited-liability company founded by the Research Foundation for the State University of New York on behalf of Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit applied science and technology organization.

For more information, please click here

Contacts:
Karen McNulty Walsh
(631) 344-8350

Copyright © Brookhaven National Laboratory

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

Scientific paper: Evidence for Short-Range-Ordered Charge Stripes Far above the Charge-Ordering Transition in La1.67Sr0.33NiO4:

Fluid "Stripes" May Be Essential for High-Temperature Superconductivity:

More Evidence for "Stripes" in High-Temperature Superconductors:

Related News Press

News and information

Sunblock poses potential hazard to sea life August 20th, 2014

Rice physicist emerges as leader in quantum materials research: Nevidomskyy wins both NSF CAREER Award and Cottrell Scholar Award August 20th, 2014

Graphene may be key to leap in supercapacitor performance August 20th, 2014

Newly-Developed Nanobiosensor Quickly Diagnoses Cancer August 20th, 2014

Laboratories

Promising Ferroelectric Materials Suffer From Unexpected Electric Polarizations: Brookhaven Lab scientists find surprising locked charge polarizations that impede performance in next-gen materials that could otherwise revolutionize data-driven devices August 18th, 2014

Research of Empa scientists on the cover of "Nature": Synthesis of structurally pure carbon nanotubes using molecular seeds August 7th, 2014

FEI Reports New Advances in Neuroscience in Collaboration with NIH: Using cryo-electron microscopy, researchers determine the structural mechanism of glutamate receptors – an important insight to the brain’s memory formation and learning August 4th, 2014

New Method Provides Nanoscale Details of Electrochemical Reactions in Electric Vehicle Battery Materials August 4th, 2014

Nanostructured metal-oxide catalyst efficiently converts CO2 to methanol: Highly reactive sites at interface of 2 nanoscale components could help overcome hurdle of using CO2 as a starting point in producing useful products July 31st, 2014

Superconductivity

Study finds physical link to strange electronic behavior: Neutron measurements offer new clues about iron-based superconductor July 31st, 2014

UCF Nanotech Spinout Developing Revolutionary Battery Technology: Power the Next Generation of Electronics with Carbon July 23rd, 2014

Flashes of light on the superconductor: Using light to modulate the properties of a copper-based superconductor July 15th, 2014

Govt.-Legislation/Regulation/Funding/Policy

Success in Intracellular Imaging of Cesium Distribution in Plants Used for Cesium Absorption August 19th, 2014

Electrical engineers take major step toward photonic circuits: Team invents non-metallic metamaterial that enables them to 'compress' and contain light August 19th, 2014

Promising Ferroelectric Materials Suffer From Unexpected Electric Polarizations: Brookhaven Lab scientists find surprising locked charge polarizations that impede performance in next-gen materials that could otherwise revolutionize data-driven devices August 18th, 2014

Novel chip-based platform could simplify measurements of single molecules: A nanopore-gated optofluidic chip combines electrical and optical measurements of single molecules onto a single platform August 14th, 2014

Discoveries

Sunblock poses potential hazard to sea life August 20th, 2014

Rice physicist emerges as leader in quantum materials research: Nevidomskyy wins both NSF CAREER Award and Cottrell Scholar Award August 20th, 2014

Newly-Developed Nanobiosensor Quickly Diagnoses Cancer August 20th, 2014

Ultrasonic Waves Applied in Production of Graphene Nanosheets August 20th, 2014

Announcements

Rice physicist emerges as leader in quantum materials research: Nevidomskyy wins both NSF CAREER Award and Cottrell Scholar Award August 20th, 2014

Graphene may be key to leap in supercapacitor performance August 20th, 2014

Newly-Developed Nanobiosensor Quickly Diagnoses Cancer August 20th, 2014

Ultrasonic Waves Applied in Production of Graphene Nanosheets August 20th, 2014

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals

Sunblock poses potential hazard to sea life August 20th, 2014

Newly-Developed Nanobiosensor Quickly Diagnoses Cancer August 20th, 2014

Ultrasonic Waves Applied in Production of Graphene Nanosheets August 20th, 2014

The channel that relaxes DNA: Relaxing DNA strands by using nano-channels: Instructions for use August 20th, 2014

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More














ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE