In materials science, electric and magnetic effects have usually been studied separately. There are, however, extraordinary materials called “multiferroics”, in which electric and magnetic excitations are closely linked. Scientists in Austria have now shown in an experiment that magnetic properties and excitations can be influenced by an electric voltage.
Converting solar energy into storable fuel remains...
In leaves, two proteins are responsible for...
A new technique that allows curved surfaces to...
New work by researchers at Univ. of California, Berkeley could soon transform the building blocks of modern electronics by making nanomagnetic switches a viable replacement for the conventional transistors found in all computers.
Researchers from North Carolina State Univ. have, for the first time, integrated a material called bismuth ferrite (BFO) as a single crystal onto a silicon chip, opening the door to a new generation of multifunctional, smart devices. Integrating the BFO into the silicon substrate as a single crystal makes the BFO more efficient by limiting the amount of electric charge that “leaks” out of the BFO into the substrate.
Ferroelectric materials are known for their ability to spontaneously switch polarization when an electric field is applied. An Oak Ridge National Laboratory-led team took advantage of this property to draw areas of switched polarization called domains on the surface of a ferroelectric material. To the researchers’ surprise, the domains began forming complex and unpredictable patterns that the researchers say should not be possible.
Batteries that power electric cars have problems. They take a long time to charge. The charge doesn’t hold long enough to drive long distances. They don’t allow drivers to quickly accelerate. They are big and bulky. By creating nanoparticles with controlled shape, engineers in California believe smaller, more powerful and energy-efficient batteries for vehicles can be built.
A team of scientists have demonstrated new application of graphene using positive feedback. Using graphene’s electrical conduction, Columbia Univ. engineers have created a nano-mechanical system that can create FM signals. It is, in effect, the world's smallest FM radio transmitter.
Tiny electrical wires protrude from some bacteria and contribute to rock and dirt formation. Pacific Northwest National Laboratory researchers studying the protein that makes up one such wire have determined the protein's structure and have shown that the protein's shape and form suggest possible ways for the bacteria to shuttle electrons along the nanowire.
Researchers from the Univ. of Pennsylvania and Drexel Univ. have experimentally demonstrated a new method for solar cell construction which may ultimately make them less expensive, easier to manufacture and more efficient at harvesting energy from the sun. The breakthrough, which is the result of five years of focused research, relies on specifically designed perovskite crystals that deliver a “bulk” photovoltaic effect.
Researchers at the Georgia Institute of Technology have recently demonstrated an integrated rhombic gridding based triboelectric nanogenerator, or “TENG”, that has been proven to be a cost-effective and robust approach for harvesting ambient environmental energy.
The Swiss Federal Institute of Technology in Lausanne’s new convention center, opening in April 2014, is being equipped with a glass façade composed of dye solar cells. The project, a world’s first for an exterior window, leverages the potential of dye-sensitive solar cells known as Graetzel cells, which are indifferent to the angle of incidence of light that hits them.
Univ. of Delaware materials scientists have successfully developed a compact, stretchable wire-shaped supercapacitor based on continuous carbon nanotube fibers. When subjected to a tensile strain of 100% over 10,000 charge/discharge cycles, the CNT supercapacitor’s electrochemical performance improved to 108%.
Researchers in Basque country in Spain have developed and patented a new source of light emitter based on boron nitride nanotubes. Suitable for developing high-efficiency optoelectronic devices, the structural defects in the nanotubes help make it extremely efficient in ultraviolet light emission.
Quantum dots are nano-sized semiconductor particles whose emission color can be tuned by simply changing their dimensions. New research at Los Alamos National Laboratory aims to improve quantum dot-based light-emitting diodes by using a new generation of engineered quantum dots tailored specifically to have reduced wasteful charge-carrier interactions that compete with the production of light.
Semiconductor Research Corporation (SRC) has launched a new research program on hybrid bio-semiconductor systems that they hope will provide insights and opportunities for future information and communication technologies. The Semiconductor Synthetic Biology (SSB) program will initially fund research at six universities.
Amy Prieto, a chemist at Colorado State Univ. leads a start-up company with the goal of developing a lithium-ion battery that should be safer, cheaper, faster-charging, and more environmentally friendly than conventional batteries now on the market. The key to the technology is copper foam which is easy to manufacture and has high power density.
In new research, scientists have demonstrated that the efficiency of all solar panel designs could be improved by up to 22% by covering their surface with aluminium studs that bend and trap light inside the absorbing layer. At the microscopic level, the studs make the surface of the solar panels look similar to the interlocking building bricks played with by children across the world.
Although the amount of data that can be stored has increased immensely during the past few decades, it is still difficult to actually store data for a long period of time. A researcher has recently demonstrated a way to store data for extremely long periods, even millions of years, using an etched wafer made of tungsten encapsulated by silicon nitride. The material is resistant to both time and elevated temperatures.
Vanadium dioxide is one of the few known materials that acts like an insulator at low temperatures but like a metal at warmer temperatures starting around 67 C. This temperature-driven metal-insulator transition, the origin of which is still intensely debated, could be induced by the application of an external electric field. Beamline studies at the Advanced Light Source has shed some light on this potential avenue for faster electronics.
People often customize the size and shape of materials like textiles and wood without turning to specialists like tailors or carpenters. In the future this should be possible with electronics, according to computer scientists who have developed a printable multi-touch sensor whose shape and size can be altered by anybody.
Renewable sources like sun and wind aren’t always productive. But waves in the ocean are never still, prompting Georgia Institute of Technology scientists to find a way to produce energy by making use of contact electrification between a patterned plastic nanoarray and water. They have introduced an inexpensive and simple prototype of a triboelectric nanogenerator that could be used to produce energy and as a chemical or temperature sensor.
Researchers in Japan have developed a new photodiode that can detect in just milliseconds a certain type of high-energy ultraviolet light, called UVC, which is powerful enough to break the bonds of DNA and harm living creatures. The new device shows promise for space-based communication and monitoring ozone depletion.
Researchers in Germany are showing the way toward low-cost, industrial-scale manufacturing of a new family of electronic devices. Gas sensors that could be integrated into food packaging to gauge freshness, new types of solar cells and flexible transistors, and sensors that could be built into electronic skin: All can be made with carbon nanotubes, sprayed like ink onto flexible plastic sheets or other substrates.
A new, environmentally-friendly electronic alloy consisting of 50 aluminum atoms bound to 50 atoms of antimony may be promising for building next-generation "phase-change" memory devices. Phase-change memory is being actively pursued as an alternative to the ubiquitous flash memory for data storage applications, because flash memory is limited in its storage density and phase-change memory can operate much faster.
Using colloidal lead sulfide nanocrystal quantum dot (QD) substances, U.S. Naval Research Laboratory (NRL) research scientists and engineers have recorded an open-circuit voltage of 692 mV using the QD bandgap of a 1.4 eV under one-sun illumination. The achievement highlights the potential for improvements in QD solar cells by employing smaller quantum dots.
Measuring the band offset faced by electrons jumping from one material to another is a key component of a nanoscale design process because it guides redesign and prototyping. Current methods don’t work on the nanoscale, however. Using laser-induced current in a nanowire device and its dependence on the wavelength of the laser, a team at Drexel Univ. devised a new method to derive the band offset.
Electronic devices with touchscreens rely on transparent conductors made of indium tin oxide, or ITO. But cost and the physical limitations of this material are limiting progress in developing flexible touchscreens. A research collaboration between the Univ. of Pennsylvania and Duke Univ. is exploring the use of nanowires to replace ITO, and are using simulation tools to determine how they might work.
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