A recent study from Lawrence Berkeley National Laboratory offers the first direct observations and recordings of how electrons and holes respond to a charged impurity—a single Coulomb potential—placed on a gated graphene device. The results provide experimental support to the theory that interactions between electrons are critical to graphene’s extraordinary properties.
A research team has built an air-breathing battery that uses the chemical energy generated by the oxidation of iron plates that are exposed to the oxygen in the air—a process similar to rusting. The concept has been around for decades, but competing chemical reaction of hydrogen generation sucked away about 50% of the battery’s energy. Recent breakthroughs have lowered this loss to just 4%.
Computers often do not run as fast as they should because they are constantly transferring information between two kinds of memory: a fast, volatile memory connected to the CPU, and a slow, non-volatile memory that remembers data even when switched off. A special class of universal memory called spin-transfer torque magnetic random access memory (MRAM) being explored by researchers in Singapore could help avoid this bottleneck.
Plastic semiconductors have an important design flaw: The electronic current is influenced by poorly understood "charge traps" in the material. A new study by an international team of researchers reveals a common mechanism underlying these traps and provides a theoretical framework to design trap-free plastic electronics.
In a first for nanotechnology, a biophysicist in Switzerland has developed a method that measures not only the size of the particles but also their electrostatic charge. Up until the invention of this new approach, which relies on an “electrostatic trap”, it has not been possible to determine the charge of the particles directly.
Using a new side-view imaging technique, scientists in the U.K. have shown that their method for sandwiching individual graphene sheets between insulating layers in order to produce electrical devices works almost perfectly, even when more than 10 different layers are used to build the stack.
Researchers reporting fabrication of magnetic tunnel junctions using graphene between two ferromagnetic metal layers have demonstrated, for the first time, the use of graphene as a tunnel barrier—an electrically insulating barrier between two conducting materials through which electrons tunnel quantum mechanically. They accomplished the feat using a fully scalable photolithographic process.
Researchers from the University of Toronto and King Abdullah University of Science & Technology in Saudi Arabia have made a breakthrough in the development of colloidal quantum dot (CQD) films, reaching 7.0% in conversion efficiency. A combination of organic and inorganic chemistry was used to produce the most efficient CQD solar cell ever, an improvement of 37% over previous efforts.
Developed at RIKEN in Japan, a new type of transistor harnessing strong electron correlations can actually enable electrical switching of the state of matter. The device uses the electrostatic accumulation of electrical charge on the surface of a strongly-correlated material to trigger bulk switching of electronic state.
Ion irradiation creates an asymmetric potential or 'ratchet' for the main walls (visualised as light yellow spheres). The bit with a magnetic coating is shifted one position to
“Aerographite”, a jet-black network of porous, interwoven carbon tubes invented in northern Germany, weighs just 0.2 mg per cubic centimeter. This makes it 75 times lighter than Styrofoam, yet it is strong, ductile, and electrically conductive. It can also be compressed up to 95% and be pulled back to form without damage.
With the placement of a sheet of graphene, researchers at Columbia University have transformed an originally passive photonic integrated circuit into an active generator of microwave photonic signals. The device performs parametric wavelength conversion at telecommunication wavelengths, offering a glimpse at communications using very little power.
According to a Case Western Reserve University researcher, fuel cells are inefficient because the catalyst most commonly used to convert chemical energy to electricity is made of the wrong material. Platinum, he says, is like putting a resistor in the system. He also says existing explanations as to why platinum is the wrong material don’t do enough to explain its drawbacks.
A team of researchers from Drexel University has pioneered a new method for quickly and efficiently storing large amounts of electrical energy. Their solution is an electrochemical flow capacitor, which combines the strengths of batteries and supercapacitors while also negating the scalability problem.
A multi-institutional team has created the first artificial molecules whose chirality can be rapidly switched from a right-handed to a left-handed orientation with a beam of light. The breakthrough has potentially significant implications for the application of terahertz technologies across a wide range of fields, including reduced energy use for data-processing, homeland security, and ultrahigh-speed communications.
One bit of digital information stored on a hard disk currently consists of about 3 million magnetic atoms. Researchers in Germany and Japan have now developed a magnetic memory with one bit per molecule. Using an electric pulse deliver by atomic force microscopy, the metal-organic molecule can be switched reliably between a conductive, magnetic state and a low-conductive, non-magnetic state.
Researchers at Northwestern University, working with a team of scientists from the United States and abroad, have recently developed a type of electronics that can bend and stretch to more than 200% their original size, four times greater than is possible with today’s technology. The key is a combination of a porous polymer and liquid metal.
Imagine a kerosene lamp that continued to shine after the fuel was spent. Materials scientists at Harvard University have demonstrated an equivalent feat in clean energy generation with a solid-oxide fuel cell that converts hydrogen into electricity but can also store electrochemical energy like a battery. This fuel cell can continue to produce power for a short time after its fuel has run out.
Physicists in Germany have recently provided new insights into spintronics: In ultra-thin topological insulators, they have identified spin-polarized currents, which were first theoretically predicted six years ago. They have also presenteda method of application for the development of new computers.
In a search for an inexpensive alternative to platinum, a team including researchers from Oak Ridge National Laboratory turned to carbon to develop a multi-walled carbon nanotube complex that consists of cylindrical sheets of carbon. The complex featured the desired properties, but researchers didn’t know why until they tried an innovative mix of electron imaging and spectroscopy to understand the relationships at play.
The first purely silicon oxide-based “resistive RAM” memory chip that can operate in ambient conditions has been developed by researchers in the U.K., and it needs just a thousandth of the energy of Flash-based chips. Unlike other attempts to develop similar silicon-oxide chips, this invention does not require a vacuum to operate.
With the advent of the solid-state transistor and semi-conductor-based flat panel display technology, the vacuum tube has virtually disappeared from consumer electronics. But a team of researchers in Korea and at NASA’s Ames Research Center have combined the best traits of both technologies to create a vacuum channel transistor just 150 nm long.
There's nothing worse than a shonky pool table with an unseen groove or bump that sends your shot off course. A new study has found that the same goes at the nano-scale, where the "billiard balls" are tiny electrons moving across a "table" made of the semiconductor gallium arsenide.
A French-American collaboration has developed a new combination of polymers that makes it possible to design ultra-thin films capable of self-organization with a 5-nm resolution. These hybrid copolymers are based on sugars and oil-based macromolecules. Previous attempts using nothing but oil-based molecules were limited to 20 nm in thickness.
After studies involving advanced simulations of nanoscale magnetic and materials phenomena, a team of scientists in Germany have proposed making use of magnetic moments in chains of iron atoms to allow information to be transported on the nanoscale in a fast and energy-efficient manner. The scheme, demonstrated in experiments, would work over a wide temperature range, remaining largely unaffected by external magnetic fields.