Featured Research

from universities, journals, and other organizations

Novel Imaging Technique Provides First Detailed Look At Superconductor's Critical Current, Bell Labs Scientists Report

Date:
November 25, 1998
Source:
Bell Labs - Lucent Technologies
Summary:
Bell Labs researchers have produced the first microscopic pictures of a superconducting material at the precise point it no longer carries current without resistance, commonly known as its critical current. The images clearly show previously unobserved magnetic-field patterns.

MURRAY HILL, N.J -- Bell Labs researchers have produced the first microscopic pictures of a superconducting material at the precise point it no longer carries current without resistance, commonly known as its critical current. The images clearly show previously unobserved magnetic-field patterns.

"If researchers were to better explain the critical current, which is one of the most widely measured and least understood characteristics of superconductors," said physicist Dave Bishop, "it might be possible to extend the uses of superconducting materials." The research findings are described in the Nov. 26 issue of the journal Nature.

In 1986, when scientists found superconducting materials that lose all resistance to electric current at world-record high temperatures, they thought these superconductors might be used to build levitating trains and very high-speed electronic circuits. They soon discovered an obstacle, however. As the current flows through the superconducting material, it generates a magnetic field, whose whirlpool-like tubes of electric charge -- known as vortices -- can stop the current cold under certain conditions. The study of these vortices has intensified ever since.

The Bell Labs researchers imaged the vortices below, at and above the critical current to better understand the phenomena of the critical current. "At first, the vortices are stationary" Bishop said. "But at the critical current, the vortices begin to move, and this movement can impede the flow of the current. So it's crucial to understand how these vortices move and arrange themselves under various temperature and magnetic-field conditions."

The latest research reveals that when the vortices begin moving, they can form distinct patterns. "It's very similar to a flock of ducks. When they're stationary on the ground, they are arranged haphazardly. However, when they fly, they're in formation, and this pattern of flight never changes," Bishop said.

In nature, this is a common phenomenon known as dynamic pattern formation, where the static structure is disordered, but motion causes a pattern to form. The same phenomenon happens with blowing snow when the wind forms pronounced patterns in the snow, such as uniform ripples.

"While this is not a new phenomena," Bishop said, "we were surprised to find such a clear example in vortices within a superconductor."

Bishop and his colleagues at Bell Labs, which is the research and development arm of Lucent Technologies, and the Atomic Center Bariloche in Argentina made their findings by essentially "decorating" the vortices within the superconductor with microscopic iron particles. The process is similar to when children place iron filings on a piece of paper and then move them by shifting a magnet beneath the paper.

To perform the magnetic decoration, the researchers applied a magnetic field -- roughly 10 to 100 times stronger than the Earth's magnetic field -- to a superconductor carrying a current. By decorating the vortices below, at and above the critical current, the researchers were able to observe many unexpected patterns in the vortices.

However, Bishop cautioned against believing a breakthrough is imminent. "Understanding these materials is one of the greatest challenges in science, and we still have a long way to go," he said. "These results, while very exciting, represent only one piece in a very complicated puzzle."

The other authors on the Nature article include Peter Gammel, Ernst Bucher and Flavio Pardo of Bell Labs and Francisco de la Cruz of the Atomic Center Bariloche.

Lucent Technologies (LU) designs, builds, and delivers a wide range of public and private networks, communications systems and software, consumer and business telephone systems and microelectronics components. Bell Labs is the research and development arm of the company. For more information about Lucent Technologies, headquartered at Murray Hill, N.J., visit our website at http://www.lucent.com.


Story Source:

The above story is based on materials provided by Bell Labs - Lucent Technologies. Note: Materials may be edited for content and length.


Cite This Page:

Bell Labs - Lucent Technologies. "Novel Imaging Technique Provides First Detailed Look At Superconductor's Critical Current, Bell Labs Scientists Report." ScienceDaily. ScienceDaily, 25 November 1998. <www.sciencedaily.com/releases/1998/11/981125140511.htm>.
Bell Labs - Lucent Technologies. (1998, November 25). Novel Imaging Technique Provides First Detailed Look At Superconductor's Critical Current, Bell Labs Scientists Report. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/1998/11/981125140511.htm
Bell Labs - Lucent Technologies. "Novel Imaging Technique Provides First Detailed Look At Superconductor's Critical Current, Bell Labs Scientists Report." ScienceDaily. www.sciencedaily.com/releases/1998/11/981125140511.htm (accessed July 23, 2014).

Share This




More Matter & Energy News

Wednesday, July 23, 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