Navigation Links
Conducting ferroelectrics may be key to new electronic memory
Date:4/25/2011

OAK RIDGE, Tenn., April 25, 2011 - 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.


'/>"/>

Contact: Morgan McCorkle
mccorkleml@ornl.gov
865-574-7308
DOE/Oak Ridge National Laboratory
Source:Eurekalert

Related biology technology :

1. Scientists engineer superconducting thin films
2. PAREXEL Expert to Address Key Aspects of Conducting Clinical Trials in China at 7th Annual Partnerships in Clinical Trials Congress
3. Semiconducting nanotubes produced in quantity at Duke
4. Waukesha Electric partners with SuperPower and UH to build fault current limiting superconducting transformer for Dept. of Energy
5. MIT scientists transform polyethylene into a heat-conducting material
6. Bottoms up: Better organic semiconductors for printable electronics
7. Free White Paper Now Available: How to get the most from your visit to electronica 2008 in Munich
8. BioElectronics Corp Aggressively Expands Sales into Middle East
9. BioElectronics Corp. Announces $400,000 in New Orders From the Middle East
10. Akaza Research Releases New Version of OpenClinica Electronic Data Capture (EDC) Software; Targets Industry Clinical Trials
11. SAFC Hitech(TM) Expands Electronic Materials Portfolio With the Introduction of Scintillation Crystal Growth Halides
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/27/2016)... Ginkgo Bioworks , a leading organism design company ... as one of the World Economic Forum,s Technology ... companies. Ginkgo Bioworks is engineering biology to manufacture ... the nutrition, health and consumer goods sectors. The ... Fortune 500 companies to design microbes for their ...
(Date:6/24/2016)... ... June 24, 2016 , ... While the majority of commercial spectrophotometers and fluorometers ... the 6000i models are higher end machines that use the more unconventional z-dimension of ... beam from the bottom of the cuvette holder. , FireflySci has developed several ...
(Date:6/23/2016)... ... June 23, 2016 , ... ... announce the launch of their brand, UP4™ Probiotics, into Target stores nationwide. The ... is proud to add Target to its list of well-respected retailers. This list ...
(Date:6/23/2016)... , June 23, 2016 A person commits a ... crime scene to track the criminal down. An ... Food and Drug Administration (FDA) uses DNA evidence to track ... Sound far-fetched? It,s not. The FDA has increasingly ... support investigations of foodborne illnesses. Put as simply as possible, ...
Breaking Biology Technology:
(Date:6/22/2016)... , June 22, 2016 On Monday, ... call to industry to share solutions for the Biometric ... U.S. Customs and Border Protection (CBP), explains that CBP ... are departing the United States , ... and to defeat imposters. Logo - ...
(Date:6/9/2016)... ISTANBUL , June 9, 2016  Perkotek an innovation leader in attendance control ... to seamlessly log work hours, for employers to make sure the right employees are ... Logo - http://photos.prnewswire.com/prnh/20160609/377486LOGO ... ... ...
(Date:6/2/2016)... 2, 2016   The Weather Company , an IBM ... an industry-first capability in which consumers will be able to ... ask questions via voice or text and receive relevant information ... Marketers have long sought an advertising solution that ... be personal, relevant and valuable; and can scale across millions ...
Breaking Biology News(10 mins):