Featured Research

from universities, journals, and other organizations

Conducting ferroelectrics may be key to new electronic memory

Date:
April 26, 2011
Source:
DOE/Oak Ridge National Laboratory
Summary:
Novel properties of ferroelectric materials are moving scientists one step closer to realizing a new paradigm of electronic memory storage.

Novel properties of ferroelectric materials discovered at the Department of Energy's Oak Ridge National Laboratory are moving scientists one step closer to realizing a new paradigm of electronic memory storage.

A new study led by ORNL's Peter Maksymovych and published in the American Chemical Society's Nano Letters revealed that contrary to previous assumptions, domain walls in ferroelectric materials act as dynamic conductors instead of static ones.

Domain walls, the separation zones only a few atoms wide between opposing states of polarization in ferroelectric materials, are known to be conducting, but the origin of the conductivity has remained unclear.

"Our measurements identified that subtle and microscopically reversible distortions or kinks in the domain wall are at the heart of the dynamic conductivity," Maksymovych said. "The domain wall in its equilibrium state is not a true conductor like a rigid piece of copper wire. When you start to distort it by applying an electric field, it becomes a much better conductor."

Ferroelectrics, a unique class of materials that respond to the application of an electric field by microscopically switching their polarization, are already used in applications including sonar, medical imaging, fuel injectors and many types of sensors.

Now, researchers want to push the boundaries of ferroelectrics by making use of the materials' properties in areas such as memory storage and nanoelectronics. Gaining a detailed understanding of electrical conductance in domain walls is seen as a crucial step toward these next generation applications.

"This study shows for the first time that the dynamics of these defects -- the domain walls -- are a much richer source of memory functionality," Maksymovych said. "It turns out you can dial in the level of the conductivity in the domain wall, making it a tunable, metastable, dynamic memory element."

The domain wall's tunable nature refers to its delayed response to changes in conductivity, where shutting off an electric field does not produce an immediate drop in conductance. Instead, the domain wall "remembers" the last level of conductance for a given period of time and then relaxes to its original state, a phenomenon known as memristance. This type of behavior is unlike traditional electronics, which rely on silicon transistors that act as on-off switches when electric fields are applied.

"Finding functionality intrinsic to nanoscale systems that can be controlled in a novel way is not a path to compete with silicon, but it suggests a viable alternative to silicon for a new paradigm in electronics," Maksymovych said.

The ORNL-led team focused on bismuth ferrite samples, but researchers expect that the observed properties of domain walls will hold true for similar materials.

"The resulting memristive-like behavior is likely to be general to ferroelectric domain walls in semiconducting ferroelectric and multiferroic materials," said ORNL co-author Sergei Kalinin.

The samples used in the study were provided by the University of California at Berkeley. Other authors are ORNL's Arthur Baddorf, Jan Seidel and Ramamoorthy Ramesh of Lawrence Berkeley National Laboratory and UC Berkeley, and Pennsylvania State University's Pingping Wu and Long-Qing Chen.

Part of this work was supported by the Center for Nanophase Materials Sciences at ORNL.


Story Source:

The above story is based on materials provided by DOE/Oak Ridge National Laboratory. Note: Materials may be edited for content and length.


Journal Reference:

  1. Peter Maksymovych, Jan Seidel, Ying Hao Chu, Pingping Wu, Arthur P. Baddorf, Long-Qing Chen, Sergei V. Kalinin, Ramamoorthy Ramesh. Dynamic Conductivity of Ferroelectric Domain Walls in BiFeO3. Nano Letters, 2011; 110412163353015 DOI: 10.1021/nl104363x

Cite This Page:

DOE/Oak Ridge National Laboratory. "Conducting ferroelectrics may be key to new electronic memory." ScienceDaily. ScienceDaily, 26 April 2011. <www.sciencedaily.com/releases/2011/04/110425153631.htm>.
DOE/Oak Ridge National Laboratory. (2011, April 26). Conducting ferroelectrics may be key to new electronic memory. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2011/04/110425153631.htm
DOE/Oak Ridge National Laboratory. "Conducting ferroelectrics may be key to new electronic memory." ScienceDaily. www.sciencedaily.com/releases/2011/04/110425153631.htm (accessed July 29, 2014).

Share This




More Matter & Energy News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Lithium Battery 'Holy Grail' Could Provide 4 Times The Power

Lithium Battery 'Holy Grail' Could Provide 4 Times The Power

Newsy (July 28, 2014) Stanford University published its findings for a "pure" lithium ion battery that could have our everyday devices and electric cars running longer. Video provided by Newsy
Powered by NewsLook.com
The Carbon Trap: US Exports Global Warming

The Carbon Trap: US Exports Global Warming

AP (July 28, 2014) AP Investigation: As the Obama administration weans the country off dirty fuels, energy companies are ramping-up overseas coal exports at a heavy price. (July 28) Video provided by AP
Powered by NewsLook.com
Shipping Crates Get New 'lease' On Life

Shipping Crates Get New 'lease' On Life

Reuters - Business Video Online (July 25, 2014) Shipping containers have been piling up as America imports more than it exports. Some university students in Washington D.C. are set to get a first-hand lesson in recycling. Their housing is being built using refashioned shipping containers. Lily Jamali reports. Video provided by Reuters
Powered by NewsLook.com
Europe's Highest Train Turns 80 in French Pyrenees

Europe's Highest Train Turns 80 in French Pyrenees

AFP (July 25, 2014) Europe's highest train, the little train of Artouste in the French Pyrenees, celebrates its 80th birthday. Duration: 01:05 Video provided by AFP
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