Featured Research

from universities, journals, and other organizations

Scientists ping key material in sonar, closes gap on structural mystery

Date:
November 12, 2010
Source:
National Institute of Standards and Technology (NIST)
Summary:
Using a neutron beam as a probe, researchers have begun to reveal the crystal structure of a compound essential to technologies ranging from sonar to computer memory. Their recent work provides long-sought insight into just how a widely used material of modern technology actually works.

Using a neutron beam as a probe, researchers working at the National Institute of Standards and Technology (NIST) have begun to reveal the crystal structure of a compound essential to technologies ranging from sonar to computer memory. Their recent work provides long-sought insight into just how a widely used material of modern technology actually works.

Related Articles


The compound is a "piezoelectric," a material capable of changing one kind of energy into another -- mechanical to electrical, or vice versa. Long employed in sonar systems to detect sound waves, more recently piezoelectrics have been applied in devices that require minuscule changes in position, such as the head that reads data from your computer's hard drive.

For decades, the industry standard piezoelectric has been PZT, a compound that contains titanium,zirconium, lead and oxygen. Crystals of PZT change a tiny fraction of a percent in size when a sound wave strikes them, and thisshape change creates an electrical impulse. Decades ago, it was discovered that PZT performs at its best when the titanium and zirconium appear in approximately equal proportions, but no one really understood why.

"The theories frequently concern what happens at the transition line between having a surplus of zirconium and one of titanium," says Peter Gehring of the NIST Center for Neutron Research (NCNR). "Some theories suggest that right near the transition zone, the atoms take on a special configuration that allows certain atoms to move more freely than they can otherwise. But because it's been hard to grow a crystal of PZT large enough to analyze, we couldn't completely test these ideas."

A breakthrough came when chemists at Canada's Simon Fraser University managed to grow single crystals of a few millimeters in size and sent them to the NCNR for examination with neutron scattering -- a technique for determining the positions of individual atoms in a complex crystal structure by observing the patterns made by neutrons bouncing off it. The team, which also included researchers from the University of Oxford, the University of Tokyo, and the University of Warwick, was able to definitively rule out one of the proposed structures of PZT.

Instead, they found that each PZT crystal element likely assumes one of two possible forms that coexist within the larger crystal array. These forms are dictated by chemical composition, and they may influence how well the material performs on a large scale. Their findings also suggest that the change in behavior seen at the transition happens gradually, rather than at some sharply delineated proportion of zirconium to titanium.

Gehring says the results could be a step toward bettering PZT. "Determining the structure might give us the perspective necessary to design a piezoelectric material from first principles, instead of just playing around and seeing what works," he says. "That's what you need if you're ever going to build a better mousetrap."


Story Source:

The above story is based on materials provided by National Institute of Standards and Technology (NIST). Note: Materials may be edited for content and length.


Journal Reference:

  1. D. Phelan, X. Long, Y. Xie, Z.-G. Ye, A. Glazer, H. Yokota, P. Thomas, P. Gehring. Single Crystal Study of Competing Rhombohedral and Monoclinic Order in Lead Zirconate Titanate. Physical Review Letters, 2010; 105 (20): 207601 DOI: 10.1103/PhysRevLett.105.207601

Cite This Page:

National Institute of Standards and Technology (NIST). "Scientists ping key material in sonar, closes gap on structural mystery." ScienceDaily. ScienceDaily, 12 November 2010. <www.sciencedaily.com/releases/2010/11/101110113050.htm>.
National Institute of Standards and Technology (NIST). (2010, November 12). Scientists ping key material in sonar, closes gap on structural mystery. ScienceDaily. Retrieved February 1, 2015 from www.sciencedaily.com/releases/2010/11/101110113050.htm
National Institute of Standards and Technology (NIST). "Scientists ping key material in sonar, closes gap on structural mystery." ScienceDaily. www.sciencedaily.com/releases/2010/11/101110113050.htm (accessed February 1, 2015).

Share This


More From ScienceDaily



More Matter & Energy News

Sunday, February 1, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Russian Pilot Recalls Successful Balloon Flight

Russian Pilot Recalls Successful Balloon Flight

AP (Feb. 1, 2015) American Troy Bradley and Russian Leonid Tiukhtyaev landed a helium-filled balloon four miles offshore in Baja California Sur. (Feb. 1) Video provided by AP
Powered by NewsLook.com
Smart Glasses Augment Reality to Help Visually Impaired

Smart Glasses Augment Reality to Help Visually Impaired

Reuters - Innovations Video Online (Feb. 1, 2015) New augmented reality smart glasses developed by researchers at Oxford University can help people with visual impairments improve their vision by providing depth-based feedback, allowing users to "see" better. Joel Flynn reports. Video provided by Reuters
Powered by NewsLook.com
Madrid’s LED Bulbs Are Street Lights That Save

Madrid’s LED Bulbs Are Street Lights That Save

Reuters - Innovations Video Online (Feb. 1, 2015) Madrid swaps its street light system with LED technology in the largest urban street lighting replacement plan in the world. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
Nanoscale Sensor Could Help Wine Producers and Clinical Scientists

Nanoscale Sensor Could Help Wine Producers and Clinical Scientists

Reuters - Innovations Video Online (Jan. 30, 2015) A nanosensor that mimics the oral effects and sensations of drinking wine has been developed by Danish and Portuguese researchers. Jim Drury saw it in operation. 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:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

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