Featured Research

from universities, journals, and other organizations

Opposing phenomena possible key to high-efficiency electricity delivery

Date:
December 19, 2013
Source:
Princeton University
Summary:
Researchers report that the coexistence of two opposing phenomena might be the secret to understanding how materials known as high-temperature superconductors -- heralded as the future of powering our homes and communities -- actually work. Such insight could help spur the further development of high-efficiency electric-power delivery.

Princeton University-led researchers report that the coexistence of two opposing phenomena might explain how materials known as high-temperature superconductors, which are heralded as the future of powering our homes and communities, actually work. The researchers found that electrons in copper oxide high-temperature superconductors — a copper-oxygen compound prized for making power lines because of its ability to conduct electricity with no resistance — can organize into a fixed pattern known as a charge-order state, or, at a low enough temperature, move freely as superconducting pairs to carry electricity without resistance. The researchers uniquely combined atomic-scale microscopy (front image) and a new sensitive X-ray scattering technique (rear image) to visualize the structure of the charge-order state in copper oxide and its relationship with superconductivity. The image shows that the two techniques reveal unique yet complementary images of the same charge-order state, thereby demonstrating its existence in copper oxide. The junction where the charge-order and superconducting states coexist could help scientists further develop and control superconductivity.
Credit: Image courtesy of Ali Yazdani, Department of Physics

The coexistence of two opposing phenomena might be the secret to understanding the enduring mystery in physics of how materials heralded as the future of powering our homes and communities actually work, according to Princeton University-led research. Such insight could help spur the further development of high-efficiency electric-power delivery.

Published in the journal Science, the findings provide a substantial clue for unraveling the inner workings of high-temperature superconductors (HTS) based on compounds containing copper and oxygen, or copper oxides. Copper-oxide high-temperature superconductors are prized as a material for making power lines because of their ability to conduct electricity with no resistance. It's been shown that the material can be used to deliver electrical power like ordinary transmission lines, but with no loss of energy. In addition, typical superconductors need extremely low temperatures of roughly -243 degrees Celsius (-405 degrees Fahrenheit) to exhibit this 100-percent efficiency. A copper oxide HTS, however, can reach this level of efficiency at a comparatively toasty -135 degrees Celsius (-211 degrees Fahrenheit), which is achievable using liquid nitrogen.

Copper oxides are the linchpin of the world's first superconducting electrical line, the 600-meter (1,970-foot) cable installed on Long Island in 2008 as the Holbrook Superconductor Project funded by the U.S. Department of Energy. The cable is chilled with about 49,000 liters (13,000 gallons) of liquid nitrogen. Another 3 million meters (1,860 miles) of superconducting cables are bound for a power grid in South Korea.

Despite the promise and burgeoning commercial embrace of HTS materials, scientists still do not fully understand many of the properties of these compounds, including how superconductivity occurs at such high temperatures, said Ali Yazdani, a Princeton physics professor and the Science paper's senior author. That knowledge gap has hindered the development of additional HTC materials as well as efforts to increase further the temperature at which superconductivity can occur, Yazdani said.

The secret to high-temperature superconductivity may lie at the junction of that state and its near opposite, Yazdani and his colleagues found. The researchers report that high-temperature superconductivity in copper oxides forms as the material is cooled from a state in which electrons exhibit what is normally considered a competing behavior called "charge ordering." In a superconductor, electrons overcome their repulsion and form pairs that move in unison and conduct electricity without resistance. In a charge-ordered state, interaction between electrons keeps them locked into a rigid pattern, which usually limits their ability to make the freely moving pairs required for superconductivity.

"Charge ordering is when every electron knows its place and stays there -- in a superconductor, they know their place but they move in unison," Yazdani said. "It's almost like they freeze into this patterned charge-order state, and just before they become stuck they change their minds and do exactly the opposite."

The researchers' finding provides an important indication about the point at which a material potentially becomes an HTS, Yazdani said. From there, scientists may one day figure out how to enhance superconductivity, possibly even determining how it can occur at higher temperatures, he said.

There has been a previous indication of the interplay between the charge-order and superconducting states. Yazdani and his co-authors, however, combined atomic-scale microscopy and a new sensitive X-ray scattering technique to demonstrate that this phenomenon is ubiquitous across different families of copper-oxide superconductors. Their approach also presented a new method for visualizing the structure of a charge-order state and for more precisely identifying the state's relationship with superconductivity.

"Understanding and improving the properties of these materials is one of the grand challenges of our field," Yazdani said. "To make a charge-order state you use the same ingredients as a superconductor but at some point the electrons bifurcate into a state you want and the one you don't. In order to understand the one you want, you need to understand where they both came from."


Story Source:

The above story is based on materials provided by Princeton University. Note: Materials may be edited for content and length.


Journal Reference:

  1. E. H. d. S. Neto, P. Aynajian, A. Frano, R. Comin, E. Schierle, E. Weschke, A. Gyenis, J. Wen, J. Schneeloch, Z. Xu, S. Ono, G. Gu, M. Le Tacon, A. Yazdani. Ubiquitous Interplay between Charge Ordering and High-Temperature Superconductivity in Cuprates. Science, 2013; DOI: 10.1126/science.1243479

Cite This Page:

Princeton University. "Opposing phenomena possible key to high-efficiency electricity delivery." ScienceDaily. ScienceDaily, 19 December 2013. <www.sciencedaily.com/releases/2013/12/131219142309.htm>.
Princeton University. (2013, December 19). Opposing phenomena possible key to high-efficiency electricity delivery. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2013/12/131219142309.htm
Princeton University. "Opposing phenomena possible key to high-efficiency electricity delivery." ScienceDaily. www.sciencedaily.com/releases/2013/12/131219142309.htm (accessed July 24, 2014).

Share This




More Matter & Energy News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) Video provided by AP
Powered by NewsLook.com
Boeing Ups Outlook on 52% Profit Jump

Boeing Ups Outlook on 52% Profit Jump

Reuters - Business Video Online (July 23, 2014) Commercial aircraft deliveries rose seven percent at Boeing, prompting the aerospace company to boost full-year profit guidance- though quarterly revenues missed analyst estimates. Bobbi Rebell reports. Video provided by Reuters
Powered by NewsLook.com
Europe's Car Market on the Rebound?

Europe's Car Market on the Rebound?

Reuters - Business Video Online (July 23, 2014) Daimler kicks off a round of second-quarter earnings results from Europe's top carmakers with a healthy set of numbers - prompting hopes that stronger sales in Europe will counter weakness in emerging markets. Hayley Platt reports. Video provided by Reuters
Powered by NewsLook.com
9/11 Commission Members Warn of Terror "fatigue" Among American Public

9/11 Commission Members Warn of Terror "fatigue" Among American Public

Reuters - US Online Video (July 22, 2014) Ten years after releasing its initial report, members of the 9/11 Commission warn of the "waning sense of urgency" in combating terrorists attacks. Mana Rabiee reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins