By “drawing” micropatterns on nanomaterials using a focused laser beam, scientists in Singapore have modifed properties of nanomaterials for effective photonic and optoelectronic applications. Their method increased electrical conductivity and photoconductivity of the modified molybdenum disulfide material by more than 10 times and about five times respectively.
A team including scientists from Spain and from...
Together with teams from Finland and Japan,...
A research group based in Japan has developed a...
Robert Wolkow and his team at the Univ. of Alberta are working to engineer atomically precise computing technologies that have practical, real-world applications. In recent research, he and his team observed for the first time how an electrical current flows across the skin of a silicon crystal and also measured electrical resistance as the current moved over a single atomic step.
Using graphene ribbons just several atoms across, a group of researchers at the Univ. of Wisconsin-Milwaukee has found a novel way to “tune” the material, causing the extremely efficient conductor of electricity to act as a semiconductor. By imaging the ribbons with scanning-tunneling microscopy, researchers have confirmed how narrow the ribbon width must be. Achieving less than 10 nm in width is a big challenge.
An international team of physicists including researchers from the U.S. Naval Research Laboratory has used a scanning tunneling microscope to create quantum dots with identical, deterministic sizes. The perfect reproducibility of these dots opens the door to quantum dot architectures completely free of uncontrolled variations, an important goal for technologies from nanophotonics to quantum information processing.
You wouldn’t think that mechanical force could process nanoparticles more subtly than the most advanced chemistry. But researchers at Sandia National Laboratories have created a newly patented and original method that uses simple pressure to produce finer and cleaner results in forming silver nanostructures than do chemical methods, which are not only inflexible in their results but leave harmful byproducts.
An international team has developed an elegant method for producing self-organized and functionalized carbon nanolayers and equipping them chemically with a range of functions. The effort depended on the development of a special compound, the molecules of which were aligned perfectly in parallel to each other in a single self-organized layer, like the bristles on a brush.
According to researchers, a simple, scalable method of making strong, stretchable graphene oxide fibers that are easily scrolled into yarns and have strengths approaching that of Kevlar is possible. An international collaboration has recently produced graphene oxide yarn fibers much stronger than other carbon fibers.
A proposed hybrid quantum processor for a future quantum computer uses trapped atoms as the memory and superconducting qubits as the processor. The concept requires, however, an optical trap that is able to work well with superconductors, which don’t like magnetic fields or high optical power. Joint Quantum Institute scientists believe they’ve developed an effective method for creating these ultra-high transmission optical nanofibers.
Titanium dioxide nanoparticles show great promise as optical encapsulants or fillers for tunable refractive index coatings. However, they've been largely shunned because they’ve been difficult and expensive to make. Scientists at Sandia National Laboratories have now come up with an inexpensive way to synthesize properly sized titanium dioxide nanoparticles and is seeking partners who can demonstrate the process at industrial scale.
Engineers at Oregon State University have successfully shown that a continuous flow reactor can produce high-quality nanoparticles by using microwave-assisted heating. This is essentially the same force that heats up leftover food with such efficiency, but instead of warming up yesterday’s pizza, this concept may change the production of cell phones and televisions or improve solar energy systems.
The days of self-assembling nanoparticles taking hours to form a film over a microscopic-sized wafer are over. Researchers with Lawrence Berkeley National Laboratory have devised a technique whereby self-assembling nanoparticle arrays can form a highly ordered thin film over macroscopic distances in one minute.
A route for constructing protein nanomachines engineered for specific applications may now be closer to reality. Recent research has described the development of new Rosetta software that enables the design of protein nanomaterials composed of multiple copies of distinct protein subunits, which arrange themselves into higher order, symmetrical architectures. It has been used to create a nanocage, built by itself from engineered components.
Haydale, a U.K.-based developer of a unique plasma functionalization process for nanomaterials, has announced the publication of research showing its functionalized graphene nanoplatelets significantly improve the nanoscale reinforcement of resin. The report states a greater than two times increase in tensile strength and modulus of an epoxy composite using this technology.
A porous material invented by the Rice Univ. lab of chemist James Tour sequesters carbon dioxide, a greenhouse gas, at ambient temperature with pressure provided by the wellhead and lets it go once the pressure is released. The material shows promise to replace more costly and energy-intensive processes.
Imagine a tower that builds itself into the desired structure only by choosing the appropriate bricks. Absurd, but in the nano world self-assembly is now a common practice for forming structures. Researchers in Austria have been investigating how they can control the ordering of self-assembling structures and discovered how to switch the assembly process on and off.
Although the potential uses for graphene seem limitless, there has been no easy way to scale up from microscopic to large-scale applications without introducing defects. Researchers in Chicago and Korea have recently developed a supersonic spray system that produces very small droplets of graphene which disperse evenly, evaporate rapidly, and reduce aggregation tendencies. And, to the researchers’ surprise, it also eliminates defects.
Using a doped-graphene matrix to slow down and then trap atoms of the precious metal osmium, researchers in the U.K. have shown the ability to control and quantify the growth of metal-crystals. When the trapped atoms come into contact with further osmium atoms they bind together, eventually growing into 3-D metal-crystals. They have called this new technique nanocrystallometry.
Fancy Erector Set? Nope. The elaborate fractal structure shown at left is many, many times smaller than that and is certainly not child's play. It’s the latest example of a fractal nanotruss—nano because the structures are made up of members that are as thin as 5 nm; truss because they are carefully architected structures that might one day be used in structural engineering materials.
In response to requests from the semiconductor industry, a team of researchers at the Physical Measurement Laboratory has demonstrated that atomic force microscope probe tips made from its near-perfect gallium nitride nanowires are superior in many respects to standard silicon or platinum tips. They also found a way to use the tips as LEDs to illuminate sample regions while scanning.
A team in Texas has built the smallest, fastest and longest-running tiny synthetic motor to date. The reliable, 18,000-rpm device can convert electrical energy into mechanical motion on a scale 500 times smaller than a grain of salt. Made from three parts, the nanomotor can rapidly mix and pump biochemicals and move through liquids.
A new approach to integrated circuits, combining atoms of semiconductor materials into nanowires and structures on top of silicon surfaces, shows promise for a new generation of fast, robust electronic and photonic devices. Engineers in California have recently demonstrated 3-D nanowire transistors using this approach that open exciting opportunities for integrating other semiconductors, such as gallium nitride, on silicon substrates.
A research team that figured out how to coat an organic material as a thin film wanted a closer look at why their spreadable organic semiconductor grew like it did. So Cornell Univ. scientists used their high-energy synchrotron x-ray source to show how these organic molecules formed crystal lattices at the nanoscale. These high-speed movies could help advance the technology move from the laboratory to mass production.
Scientists at Ames Laboratory have developed a nanoparticle that is able to perform two processing functions at once for the production of green diesel, an alternative fuel created from the hydrogenation of oils from renewable feedstocks like algae. The method is a departure from the established process of producing biodiesel, which is accomplished by reacting fats and oils with alcohols.
Optical metamaterials harness clouds of electrons called surface plasmons to manipulate and control light. However, plasmonic devices often use gold or silver, which is incompatible with CMOS manufacturing processes. Purdue Univ. scientists have now developed an ultra-thin crystalline superlattice that instead uses metal-dielectrics. Applied using epitaxy, this “hyperbolic” film could greatly expand applications for metamaterials.
Researchers in Australia have created a micrometer thin film with record-breaking optical nonlinearity suitable for high-performance integrated photonic devices. To create the thin film the researchers spin coated graphene oxide solution to a glass surface. Using a laser as a pen they created microstructures on the graphene oxide film to tune the nonlinearity of the material.
While flexible gadgets such as “electronic skin” and roll-up touch screens are moving ever closer to reality, their would-be power sources are either too wimpy or too stiff. But that’s changing fast. Scientists have developed a new device that’s far thinner than paper, can flex and bend, and store enough energy to provide critical back-up power for portable electronics.
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