Electrical Materials
An about-face on electrical conductivity at the interface
November 15, 2011 3:40 am | News | CommentsTo improve the electronic devices that keep our world organized, scientists are on the hunt for new semiconductor materials. One answer could lie with an unusual form of electrical conductivity that takes place at the junction of two oxides. However, a group of scientists were recently surprised to find the interface of two complex oxides—the polar lanthanum chromium oxide, and the nonpolar strontium titanium oxide—did not conduct electricity.
New lithium electrode a better performer by 10-fold
November 14, 2011 1:08 pm | by Megan Fellman and Sarah Ostman | News | CommentsA team of engineers at Northwestern University has created an electrode for conventional lithium-ion batteries that allows them to both hold a charge up to 10 times greater than current technology and charge up to 10 times faster than current batteries.
World’s smallest electric car has four-“wheel”drive
November 10, 2011 11:59 am | News | CommentsDesigned by engineers in Switzerland and The Netherlands, the molecular 4x4 recently crafted from a single molecule is a billion times smaller than a VW Golf. Powered electrically by the tip of a scanning electron microscope, which stimulates each wheel separately, the “car” can travel in a straight line on a copper surface.
Robot speeds up glass development
November 7, 2011 10:28 am | News | CommentsMore and more frequently, the electronics in automobiles are being moved closer to the engine block. Materials used for these electronics must resist increasing heat, so the glass solder being used as glue must be continually optimized. For the first time ever, a robot in Germany is developing a new type of glass that can fulfill these requirements.
Physicists identify room temperature quantum bits in semiconductor
November 2, 2011 11:45 am | News | CommentsA research team has recently discovered that silicon carbide, a commonly used semiconductor, contains crystal imperfections that can be controlled at a quantum mechanical level. This level of fine-tuning might allow developers to exploit quantum physics in this material at the nanoscale.
Engineers create world's most efficient flexible OLED on plastic
October 31, 2011 7:39 am | News | CommentsOrganic light-emitting diodes (OLEDs) are currently produced using heavy-metal doped glass in order to achieve high efficiency and brightness. Engineers in Canada have re-constructed the high refractive index of these OLEDs on a plastic substrate, making the result light, flexible, and rugged.
Researchers boost LED efficiency
October 31, 2011 6:36 am | News | CommentsResearchers have used zinc oxide microwires to significantly improve the efficiency at which gallium nitride light-emitting diodes (LED) convert electricity to ultraviolet light. The devices are believed to be the first LEDs whose performance has been enhanced by the creation of an electrical charge in a piezoelectric material using the piezo-phototronic effect.
Unusual transistor made from natural cotton fibers
October 27, 2011 7:03 am | by Farhan Nuruzzaman | News | CommentsA new conformal coating technique developed at Cornell University has allowed researchers to apply gold nanoparticles and conductive polymer layers to the irregular topography of cotton fibers, creating a flexible, cotton-based transistor that is fully tunable.
Rigid restraint improves dielectric performance, lifespan
October 25, 2011 12:47 pm | News | CommentsJust as a corset improves the appearance of its wearer by keeping everything tightly together, new rigidly constraining insulating materials invented at Duke University helps prevent the inevitable microscopic breakdown of the “soft” polymers often used in their construction.
Fluoride-ion battery stores ten times the energy of lithium-ion
October 21, 2011 11:02 am | News | CommentsA new concept for a rechargeable battery has been developed by researchers in Germany. Based on a fluoride shuttle, which involves the transfer of fluoride anions between electrodes, the mechanism replaces lithium during charge transfer and allows the flow of many more electrons per metal atom.
New electrochemical cell has a plasma electrode
October 20, 2011 10:56 am | News | CommentsTypical fuel cells and batteries rely on solid metal electrodes, and under normal, ambient conditions a plasma electrode is not practical. Researchers at Case Western Reserve University, however, recently demonstrated one that does function at atmospheric temperature and pressure.
Impurity atoms introduce waves of disorder in exotic electronic material
October 18, 2011 4:37 am | News | CommentsBrookhaven National Laboratory scientists reveal how substituting just a few atoms can cause widespread disruption of the delicate electron interactions that give a particular "heavy fermion" material its unique properties, including superconductivity.
New graphene synthesis method helpful for electronics applications
October 17, 2011 1:12 pm | News | CommentsFor the electronics industry to effectively use graphene, it must first be grown selectively and in larger sheets. Materials experts at the University of California, Santa Barbara have refined a new, scalable chemical vapor deposition process that yields high-quality and high-uniformity graphene on a copper substrate.
Moving forward, spin goes sideways
October 11, 2011 1:51 pm | News | CommentsBuilding electronic devices that work without needing to actually transport electrons is a goal of spintronics researchers. A team from six research institutes in Japan and China now report they have produced a large spin current in a spintronic device called a lateral spin valve.
Graphene future could look like a Big Mac
October 10, 2011 3:41 am | News | CommentsResearchers in the UK have recently demonstrated what future electronic circuits made from graphene will probably look like. By sandwiching two sheets of graphene with another two-dimensional material, boron nitrate, the team created a graphene “Big Mac”.
Colored solar cells could make display screens more efficient
October 7, 2011 12:38 pm | News | CommentsIn traditional LCDs, less than 8% of the backlight actually reaches a viewer's eyes. The rest is absorbed by color filters and polarizers. A new kind of screen pixel has been invented that doubles as a solar cell and could greatly boost the energy efficiency of cell phones and e-readers.
Graphene shows unusual thermoelectric response to light
October 7, 2011 12:30 pm | by David L. Chandler, MIT News Office | News | CommentsMassachusetts Institute of Technology researchers have found that shining light on a sheet of graphene, treated so that it had two regions with different electrical properties, creates a temperature difference that, in turn, generates a current. Previously, this effect had been thought to be photovoltaic in nature.
New quantum spin conductors are impervious to magnetic impurities
September 30, 2011 6:55 am | News | CommentsConductors like copper heat up, limiting circuit densities. Materials that exhibit the quantum spin Hall effect offer flow without the need for heat dissipation, but they are hindered by magnetic imperfections. Researchers at RIKEN in Japan believe they’ve solved this problem.
Researchers devise world’s first energy-storage membrane
September 29, 2011 11:03 am | News | CommentsA team in Singapore has developed the world's first energy-storage membrane. Based on deposited polystyrene-based polymer technology, the soft, foldable can, when charged by two metal plates, store charge at 0.2 farads per square centimeter.
When stacked, graphene layers can be electrically tuned
September 26, 2011 1:43 pm | by Iqbal Pittalwala | News | CommentsAn accidental discovery in a physicist’s laboratory at the University of California, Riverside provides a unique route for tuning the electrical properties of graphene. Depending on the way three layers were stacked together, researchers found, graphene could become a conductor or an insulator.
Solar cell technology gives light waves “amnesia”
September 26, 2011 1:24 pm | by Jared Sagoff | News | CommentsSolar concentrators that rely on mirrors and lenses typically require expensive tracking systems. But another type of cell, a luminescent concentrator proposed by Argonne National Laboratory and Northwestern University experts, would rely on fluorescent plastic to force light to “forget” its incoming wavelength, making its energy easier to harvest.
ORNL discovers amazing electrical properties in polymers
September 22, 2011 9:24 am | News | CommentsCrystals and ceramics pale when compared to a material researchers at Oak Ridge National Laboratory discovered that has 10 times their piezoelectric effect, making it suitable for perhaps hundreds of everyday uses.
A guide to producing CIGS solar cells with record efficiency
September 21, 2011 11:40 am | News | CommentsA newly published paper from EMPA, the Swiss federal laboratory, details the steps its technology team took to build a flexible cadmium-indium-gallium-diselenide (CIGS) photovoltaic cell that would achieve a world record 18.7% efficiency rating.
Microwave ovens a key to energy production from wasted heat
September 20, 2011 9:26 am | News | CommentsMore than 60% of the energy produced by cars, machines, and industry around the world is lost as waste heat—an age-old problem—but researchers have found a new way to make "thermoelectric" materials for use in technology that could potentially save vast amounts of energy.
Ferroelectrics could pave way for ultra-low power computing
September 12, 2011 11:03 am | News | CommentsEngineers at the University of California, Berkeley, have shown that it is possible to reduce the minimum voltage necessary to store charge in a capacitor, an achievement that could reduce the power draw and heat generation of today's electronics.
