Doe Science news source
The DOE Science News Source is a Newswise initiative to promote research news from the Office of Science of the DOE to the public and news media.
  • 2017-05-09 20:05:53
  • Article ID: 674424

Scientists Help Thin-Film Ferroelectrics Go Extreme

Berkeley Lab researchers create polarization gradient, boost temperature span of ubiquitous material

  • Credit: Anoop Damodaran/Berkeley Lab

    On the left is a low-resolution scanning transmission electron microscopy (STEM) image of a ferroelectric material that is continuously graded from barium strontium titanate (BSTO, top) to barium titanate (BTO, bottom). The material is grown on a gadolinium scandate (GSO) substrate buffered by a strontium ruthenate (SRO) bottom electrode. To the right are local nanobeam diffraction-based 2D maps of a-axis and c-axis lattice parameters that confirm large strain gradients in the ferroelectric material. The material is promising as electrically-tunable capacitors with extreme temperature stability.

Scientists have greatly expanded the range of functional temperatures for ferroelectrics, a key material used in a variety of everyday applications, by creating the first-ever polarization gradient in a thin film.

The achievement, reported May 10 in Nature Communications by researchers at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab), paves the way for developing devices capable of supporting wireless communications in extreme environments, from inside nuclear reactors to Earth’s polar regions.

Ferroelectric materials are prized for having a spontaneous polarization that is reversible by an applied electric field and for the ability to produce electric charges in response to physical pressure. They can function as capacitors, transducers, and oscillators, and they can be found in applications such as transit cards, ultrasound imaging, and push-button ignition systems.

Berkeley Lab scientists created a strain and chemical gradient in a 150-nanometer-thin film of barium strontium titanate, a widely used ferroelectric material. The researchers were able to directly measure the tiny atomic displacements in the material using cutting-edge advanced microscopy at Berkeley Lab, finding gradients in the polarization. The polarization varied from 0 to 35 microcoulombs per centimeter squared across the thickness of the thin-film material.

Tossing out textbook predictions

“Traditional physics and engineering textbooks wouldn’t have predicted this observation,” said study principal investigator Lane Martin, faculty scientist at Berkeley Lab’s Materials Sciences Division and UC Berkeley associate professor of materials and engineering. “Creating gradients in materials costs a lot of energy—Mother Nature doesn’t like them—and the material works to level out such imbalances in whatever way possible. In order for a large gradient like the one we have here to occur, we needed something else in the material to compensate for this unfavorable structure. In this case, the key is the material’s naturally occurring defects, such as charges and vacancies of atoms, that accommodate the imbalance and stabilize the gradient in polarization.”

Creating a polarization gradient had the beneficial effect of expanding the temperature range for optimal performance by the ferroelectric material. Barium titanate’s function is strongly temperature-dependent with relatively small effects near room temperature and a large, sharp peak in response at around 120 degrees Celsius. This makes it hard to achieve well-controlled, reliable function as the temperature varies beyond a rather narrow window. To adapt the material to work for applications at and around room temperature, engineers tune the chemistry of the material, but the range of temperatures where the materials are useful remains relatively narrow.

"The new polarization profile we have created gives rise to a nearly temperature-insensitive dielectric response, which is not common in ferroelectric materials," said Martin. "By making a gradient in the polarization, the ferroelectric simultaneously operates like a range or continuum of materials, giving us high-performance results across a 500-degree Celsius window. In comparison, standard, off-the-shelf materials today would give the same responses across a much smaller 50-degree Celsius window."

Beyond the obvious expansions to hotter and colder environments, the researchers noted that this wider temperature range could shrink the number of components needed in electronic devices and potentially reduce the power draw of wireless phones.

"The smartphone I'm holding in my hand right now has dielectric resonators, phase shifters, oscillators—more than 200 elements altogether—based on similar materials to what we studied in this paper," said Martin. “About 45 of those elements are needed to filter the signals coming to and from your cell phone to make sure you have a clear signal. That’s a huge amount of real estate to dedicate to one function.”

Because changes in temperature alter the resonance of the ferroelectric materials, there are constant adjustments being made to match the materials to the wavelength of the signals sent from cell towers. Power is needed to tune the signal, and the more out of tune it is, the more power the phone needs to use to get a clear signal for the caller. A material with a polarization gradient capable operating over large temperatures regimes could reduce the power needed to tune the signal.

Faster detectors enable new imaging techniques

Understanding the polarization gradient entailed the use of epitaxial strain, a strategy in which a crystalline overlayer is grown on a substrate, but with a mismatch in the lattice structure. This strain engineering technique, commonly employed in semiconductor manufacturing, helps control the structure and enhance performance in materials.

Recent advances in electron microscopy have allowed researchers to obtain atomic-scale structural data of the strained barium strontium titanate, and to directly measure the strain and polarization gradient.

"We have established a way to use nanobeam scanning diffraction to record diffraction patterns from each point, and afterwards analyze the datasets for strain and polarization data," said study co-author Andrew Minor, director of the National Center for Electron Microscopy at Berkeley Lab’s Molecular Foundry, a DOE Office of Science User Facility. "This type of mapping, pioneered at Berkeley Lab, is both new and very powerful."

Another key factor was the speed of the detector, Minor added. For this paper, data was obtained at a rate of 400 frames per second, an order of magnitude faster than the 30-frame-per-second rate from just a few years ago. This technique is now available for users at the Foundry.

"We're seeing a revolution in microscopy related to the use of direct electron detectors that is changing many fields of research," said Minor, who also holds an appointment as a UC Berkeley professor of materials science and engineering. "We're able to both see and measure things at a scale that was hard to imagine until recently."

Co-lead authors of the study are postdoctoral researcher Anoop Damodaran and graduate student Shishir Pandya at UC Berkeley's Department of Materials Science and Engineering. Other study co-authors include researchers from the University of Pennsylvania, the Carnegie Institution for Science, and Rutgers University.  

This work included support from DOE's Office of Science, the Army Research Office, the National Science Foundation, the Gordon and Betty Moore Foundation and the Carnegie Institution for Science.

###

Lawrence Berkeley National Laboratory addresses the world’s most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab’s scientific expertise has been recognized with 13 Nobel Prizes. The University of California manages Berkeley Lab for the U.S. Department of Energy’s Office of Science. For more, visit www.lbl.gov.

DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

X
X
X
  • Filters

  • × Clear Filters

Cyborg Bacteria Outperform Plants When Turning Sunlight Into Useful Compounds (Video)

Photosynthesis provides energy for the vast majority of life on Earth. But chlorophyll, the green pigment that plants use to harvest sunlight, is relatively inefficient. To enable humans to capture more of the sun's energy than natural photosynthesis can, scientists have taught bacteria to cover themselves in tiny, highly efficient solar panels to produce useful compounds.

Scientists Create 'Diamond Rain' That Forms in the Interior of Icy Giant Planets

In an experiment designed to mimic the conditions deep inside the icy giant planets of our solar system, scientists were able to observe "diamond rain" for the first time as it formed in high-pressure conditions. Extremely high pressure squeezes hydrogen and carbon found in the interior of these planets to form solid diamonds that sink slowly down further into the interior.

Nanotechnology Moves From the Clean Room to the Classroom

The U.S. Department of Energy's Argonne National Laboratory and United Scientific Supplies, Inc. are introducing high school students to nanoscience with a new hands-on product.

Discovered: A Quick and Easy Way to Shut Down Instabilities in Fusion Devices

Article describes use of second neutral beam injector to suppress instabilities on the NSTX-U

Researchers Create Molecular Movie of Virus Preparing to Infect Healthy Cells

A research team has created for the first time a movie with nanoscale resolution of the three-dimensional changes a virus undergoes as it prepares to infect a healthy cell. The scientists analyzed thousands of individual snapshots from intense X-ray flashes, capturing the process in an experiment at the Department of Energy's SLAC National Accelerator Laboratory.

Nanotechnology Gives Green Energy a Green Color

Solar panels have tremendous potential to provide affordable renewable energy, but many people see traditional black and blue panels as an eyesore. Architects, homeowners and city planners may be more open to the technology if they could install colorful, efficient solar panels, and a new study, published this week in Applied Physics Letters, brings us one step closer. Researchers have developed a method for imprinting existing solar panels with silicon nanopatterns that scatter green light back toward an observer.

New 3-D Simulations Show How Galactic Centers Cool Their Jets

Scientists at Berkeley Lab and Purdue University developed new theories and 3-D simulations to explain what's at work in the mysterious jets of energy and matter beaming from the center of galaxies at nearly the speed of light.

Are Your Tweets Feeling Well?

Study finds opinion and emotion in tweets change when you get sick, a method public health workers could use to track health trends.

"Getting to 80%" on Energy Cutbacks Cannot Occur Unless Behaviors Change

California's plan to cut energy consumption by 80 percent by 2050 cannot be achieved with current proposed policy changes because most solutions focus on changing technologies rather than changing behavior, a new UC Davis study suggests.

New Battery Material Goes with the Flow

Scientists at the U.S. Department of Energy's (DOE) Argonne National Laboratory have engineered a new material to be used in redox flow batteries, which are particularly useful for storing electricity for the grid. The material consists of carefully structured molecules designed to be particularly electrochemically stable in order to prevent the battery from losing energy to unwanted reactions.


  • Filters

  • × Clear Filters

Kathryn Hastie Wins Spicer Award for Lassa Virus Work at SLAC's X-Ray Synchrotron

Kathryn Hastie, staff scientist at The Scripps Research Institute, has spent the last decade studying how the deadly Lassa virus - which causes up to half a million cases of Lassa fever each year in West Africa - enters human cells via a cell surface receptor.

Southern Research to Play Key Role in Low Cost Carbon Fiber Project

Southern Research's Energy & Environment division (E&E) will participate as a subcontractor to WRI to provide renewable acrylonitrile -- the key raw material needed to produce the highest quality carbon fibers -- produced from biomass-derived second generation sugars.

Newly Upgraded Laser Allows Scientists to Peer Further Into the Extreme Universe at SLAC's LCLS

Scientists at the Department of Energy's SLAC National Accelerator Laboratory recently upgraded a powerful optical laser system used to create shockwaves that generate high-pressure conditions like those found within planetary interiors. The laser system now delivers three times more energy for experiments with SLAC's ultrabright X-ray laser, providing a more powerful tool for probing extreme states of matter in our universe.

Three Brookhaven Lab Scientists Selected to Receive Early Career Research Program Funding

Three scientists at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory have been selected by DOE's Office of Science to receive significant research funding through its Early Career Research Program.

Upcoming 232nd ECS Meeting to Feature International Energy Summit, Nobel Laureate Lecture

The 232nd ECS Meeting will include 49 topical symposia and over 2,300 technical presentations, including the 7th International Electrochemical Energy Summit, the Society's inaugural OpenCon and Hack Day events, and plenary lecture delivered by former U.S. Secretary of Energy and Nobel Prize Laureate Steven Chu.

PNNL Scientist Jiwen Fan Receives DOE Early Career Research Award

Jiwen Fan of the Department of Energy's Pacific Northwest National Laboratory has been selected to receive a 2017 Early Career Research Program award from the U.S. Department of Energy. Fan will use the award to study severe thunderstorms in the central United States - storms that produce large hail, damaging winds, tornadoes, and torrential rainfall.

Three SLAC Scientists Receive DOE Early Career Research Grants

Three scientists at the Department of Energy's SLAC National Accelerator Laboratory will receive DOE Early Career Research Program grants for research to find evidence of cosmic inflation, understand how plasmas excite particles to high energies and develop a way to accelerate particles in much shorter distances with terahertz radiation.

Four ORNL Researchers Receive DOE Early Career Funding Awards

Four Oak Ridge National Laboratory researchers specializing in nuclear physics, fusion energy, advanced materials and environmental science are among 59 recipients of Department of Energy's Office of Science Early Career Research Program awards.

Missouri S&T Professor Earns Patent for Energy Storage Technology

ceramic engineering professor at Missouri University of Science and Technology has received a federal patent for his latest innovation, a multi-layer ceramic capacitor that could help boost energy storage in applications ranging from pulse power devices to military hardware.

James Peery Named Chief Scientist of the Global Security Directorate at Oak Ridge National Laboratory

James Peery, who has led critical national security programs at Sandia National Laboratories and Los Alamos National Laboratory, has been selected as the chief scientist of the Global Security Directorate at Oak Ridge National Laboratory.


  • Filters

  • × Clear Filters

A New Oxidation State for Plutonium

Plutonium has more verified and accessible oxidation states than any other actinide element, an important insight for energy and security applications.

A Traffic Cop for Molecules

Easily manufactured, rigid membranes with ultra-small pores provides to be ultra-selective in separating chemicals.

Creating a Molecular Super Sponge, From the Ground Up

A new uranium-based metal-organic framework, NU-1301, could aid energy producers and industry.

Physicists Move Closer to Listening in on Sub-Atomic Conversation

Calculations of a subatomic particle called the sigma provide insight into the communication between subatomic particles deep inside the heart of matter.

Meet the Director: Chuck Black

This is a continuing profile series on the directors of the Department of Energy (DOE) Office of Science User Facilities. These scientists lead a variety of research institutions that provide researchers with the most advanced tools of modern science including accelerators, colliders, supercomputers, light sources and neutron sources, as well as facilities for studying the nano world, the environment, and the atmosphere.

Making an Ultra-small Silicon "Chip"

A new polymer, created with a structure inspired by crystalline silicon, may make it easier to build better computers and solar cells.

How to Keep a Vital Diagnostic Isotope in Stock

Researchers succeed in producing larger quantities of a long-lived radioisotope, titanium-44, that generates a needed isotope, scandium-44g, on demand.

When Strontium Is Away, Iridium Comes Out to Play

Developing a highly active and acid-stable catalyst for water splitting could significantly impact solar energy technologies.

On Track Towards a Zika Virus Vaccine

Antibody's molecular structure reveals how it recognizes the Zika virus

Quantum Computing Building Blocks

Scientists invented an approach to creating ordered patterns of nitrogen-vacancy centers in diamonds, a promising approach to storing and computing quantum data.


Spotlight

Saturday May 20, 2017, 12:05 PM

Rensselaer Polytechnic Institute Graduates Urged to Embrace Change at 211th Commencement

Rensselaer Polytechnic Institute (RPI)

Monday May 15, 2017, 01:05 PM

ORNL, University of Tennessee Launch New Doctoral Program in Data Science

Oak Ridge National Laboratory

Friday April 07, 2017, 11:05 AM

Champions in Science: Profile of Jonathan Kirzner

Department of Energy, Office of Science

Wednesday April 05, 2017, 12:05 PM

High-Schooler Solves College-Level Security Puzzle From Argonne, Sparks Interest in Career

Argonne National Laboratory

Tuesday March 28, 2017, 12:05 PM

Champions in Science: Profile of Jenica Jacobi

Department of Energy, Office of Science

Friday March 24, 2017, 10:40 AM

Great Neck South High School Wins Regional Science Bowl at Brookhaven Lab

Brookhaven National Laboratory

Wednesday February 15, 2017, 04:05 PM

Middle Schoolers Test Their Knowledge at Science Bowl Competition

Argonne National Laboratory

Friday January 27, 2017, 04:00 PM

Haslam Visits ORNL to Highlight State's Role in Discovering Tennessine

Oak Ridge National Laboratory

Tuesday November 08, 2016, 12:05 PM

Internship Program Helps Foster Development of Future Nuclear Scientists

Oak Ridge National Laboratory

Friday May 13, 2016, 04:05 PM

More Than 12,000 Explore Jefferson Lab During April 30 Open House

Thomas Jefferson National Accelerator Facility

Monday April 25, 2016, 05:05 PM

Giving Back to National Science Bowl

Ames Laboratory

Friday March 25, 2016, 12:05 PM

NMSU Undergrad Tackles 3D Particle Scattering Animations After Receiving JSA Research Assistantship

Thomas Jefferson National Accelerator Facility

Tuesday February 02, 2016, 10:05 AM

Shannon Greco: A Self-Described "STEM Education Zealot"

Princeton Plasma Physics Laboratory

Monday November 16, 2015, 04:05 PM

Rare Earths for Life: An 85th Birthday Visit with Mr. Rare Earth

Ames Laboratory

Tuesday October 20, 2015, 01:05 PM

Meet Robert Palomino: 'Give Everything a Shot!'

Brookhaven National Laboratory

Tuesday April 22, 2014, 11:30 AM

University of Utah Makes Solar Accessible

University of Utah

Wednesday March 06, 2013, 03:40 PM

Student Innovator at Rensselaer Polytechnic Institute Seeks Brighter, Smarter, and More Efficient LEDs

Rensselaer Polytechnic Institute (RPI)

Friday November 16, 2012, 10:00 AM

Texas Tech Energy Commerce Students, Community Light up Tent City

Texas Tech University

Wednesday November 23, 2011, 10:45 AM

Don't Get 'Frosted' Over Heating Your Home This Winter

Temple University

Wednesday July 06, 2011, 06:00 PM

New Research Center To Tackle Critical Challenges Related to Aircraft Design, Wind Energy, Smart Buildings

Rensselaer Polytechnic Institute (RPI)

Friday April 22, 2011, 09:00 AM

First Polymer Solar-Thermal Device Heats Home, Saves Money

Wake Forest University

Friday April 15, 2011, 12:25 PM

Like Superman, American University Will Get Its Energy from the Sun

American University

Thursday February 10, 2011, 05:00 PM

ARRA Grant to Help Fund Seminary Building Green Roof

University of Chicago

Tuesday December 07, 2010, 05:00 PM

UC San Diego Installing 2.8 Megawatt Fuel Cell to Anchor Energy Innovation Park

University of California San Diego

Monday November 01, 2010, 12:50 PM

Rensselaer Smart Lighting Engineering Research Center Announces First Deployment of New Technology on Campus

Rensselaer Polytechnic Institute (RPI)

Friday September 10, 2010, 12:40 PM

Ithaca College Will Host Regional Clean Energy Summit

Ithaca College

Tuesday July 27, 2010, 10:30 AM

Texas Governor Announces $8.4 Million Award to Create Renewable Energy Institute

Texas Tech University

Friday May 07, 2010, 04:20 PM

Creighton University to Offer New Alternative Energy Program

Creighton University

Wednesday May 05, 2010, 09:30 AM

National Engineering Program Seeks Subject Matter Experts in Energy

JETS Junior Engineering Technical Society

Wednesday April 21, 2010, 12:30 PM

Students Using Solar Power To Create Sustainable Solutions for Haiti, Peru

Rensselaer Polytechnic Institute (RPI)

Wednesday March 03, 2010, 07:00 PM

Helping Hydrogen: Student Inventor Tackles Challenge of Hydrogen Storage

Rensselaer Polytechnic Institute (RPI)

Thursday February 04, 2010, 02:00 PM

Turning Exercise into Electricity

Furman University

Thursday November 12, 2009, 12:45 PM

Campus Leaders Showing the Way to a Sustainable, Clean Energy Future

National Wildlife Federation (NWF)

Tuesday November 03, 2009, 04:20 PM

Furman University Receives $2.5 Million DOE Grant for Geothermal Project

Furman University

Thursday September 17, 2009, 02:45 PM

Could Sorghum Become a Significant Alternative Fuel Source?

Salisbury University

Wednesday September 16, 2009, 11:15 AM

Students Navigating the Hudson River With Hydrogen Fuel Cells

Rensselaer Polytechnic Institute (RPI)

Wednesday September 16, 2009, 10:00 AM

College Presidents Flock to D.C., Urge Senate to Pass Clean Energy Bill

National Wildlife Federation (NWF)

Wednesday July 01, 2009, 04:15 PM

Northeastern Announces New Professional Master's in Energy Systems

Northeastern University

Friday October 12, 2007, 09:35 AM

Kansas Rural Schools To Receive Wind Turbines

Kansas State University

Thursday August 17, 2006, 05:30 PM

High Gas Prices Here to Stay, Says Engineering Professor

Rowan University

Wednesday May 17, 2006, 06:45 PM

Time Use Expert's 7-Year Fight for Better Gas Mileage

University of Maryland, College Park





Showing results

0-4 Of 2215