Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

ORNL experiments prove nanoscale metallic conductivity in ferroelectrics

10.01.2012
The prospect of electronics at the nanoscale may be even more promising with the first observation of metallic conductance in ferroelectric nanodomains by researchers at Oak Ridge National Laboratory.

Ferroelectric materials, which switch their polarization with the application of an electric field, have long been used in devices such as ultrasound machines and sensors. Now, discoveries about ferroelectrics' electronic properties are opening up possibilities of applications in nanoscale electronics and information storage.


ORNL researchers used piezoresponse force microscopy to demonstrate the first evidence of metallic conductivity in ferroelectric nanodomains. A representative nanodomain is shown in the PFM image above.

In a paper published in the American Chemical Society's Nano Letters, the ORNL-led team demonstrated metallic conductivity in a ferroelectric film that otherwise acts as an insulator. This phenomenon of an insulator-metal transition was predicted more than 40 years ago by theorists but has eluded experimental proof until now.

"This finding unambiguously identifies a new conduction channel that percolates through the insulating matrix of the ferroelectric, which opens potentially exciting possibilities to 'write' and 'erase' circuitry with nanoscale dimensions," said lead author Peter Maksymovych of ORNL's Center for Nanophase Materials Sciences.

From an applied perspective, the ability to use only an electric field as a knob that tunes both the magnitude of metallic conductivity in a ferroelectric and the type of charge carriers is particularly intriguing. Doing the latter in a semiconductor would require a change of the material composition.

"Not only can we turn on metallic conductivity, but if you keep changing the bias dials, you can control the behavior very precisely," Maksymovych said. "And the smaller the nanodomain, the better it conducts. All this occurs in the exact same position of the material, and we can go from an insulator to a better metal or a worse metal in a heartbeat or faster. This is potentially attractive for applications, and it also leads to interesting fundamental questions about the exact mechanism of metallic conductivity."

Although the researchers focused their study on a well-known ferroelectric film called lead-zirconate titanate, they expect their observations will hold true for a broader array of ferroelectric materials.

"We also anticipate that extending our studies onto multiferroics, mixed-phase and anti-ferroelectrics will reveal a whole family of previously unknown electronic properties, breaking new ground in fundamentals and applications alike," said co-author and ORNL senior scientist Sergei Kalinin.

The samples used in the study were provided by the University of California at Berkeley. Co-authors on the paper are ORNL's Arthur Baddorf, UC Berkeley's Ying-Hao Chu, Ramamoorthy Ramesh and Pu Yu, and National Academy of Science of Ukraine's Eugene Eliseev and Anna Morozovska. The full paper, "Tunable Metallic Conductance in Ferroelectric Nanodomains," is available at http://pubs.acs.org/doi/full/10.1021/nl203349b.

Part of this work was supported by the Center for Nanophase Materials Sciences at ORNL. CNMS is one of the five DOE Nanoscale Science Research Centers supported by the DOE Office of Science, premier national user facilities for interdisciplinary research at the nanoscale. Together the NSRCs comprise a suite of complementary facilities that provide researchers with state-of-the-art capabilities to fabricate, process, characterize and model nanoscale materials, and constitute the largest infrastructure investment of the National Nanotechnology Initiative. The NSRCs are located at DOE's Argonne, Brookhaven, Lawrence Berkeley, Oak Ridge and Sandia and Los Alamos national laboratories. For more information about the DOE NSRCs, please visit http://science.energy.gov/bes/suf/user-facilities/nanoscale-science-research-centers/. Work at the University of California, Berkeley, was supported by DOE's Office of Science and the Semiconductor Research Corporation. ORNL is managed by UT-Battelle for the Department of Energy's Office of Science.

Morgan McCorkle | EurekAlert!
Further information:
http://www.ornl.gov

More articles from Materials Sciences:

nachricht Reliable molecular toggle switch developed
30.03.2017 | Karlsruher Institut für Technologie (KIT)

nachricht Researchers shoot for success with simulations of laser pulse-material interactions
29.03.2017 | DOE/Oak Ridge National Laboratory

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

'On-off switch' brings researchers a step closer to potential HIV vaccine

30.03.2017 | Health and Medicine

Penn studies find promise for innovations in liquid biopsies

30.03.2017 | Health and Medicine

An LED-based device for imaging radiation induced skin damage

30.03.2017 | Medical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>