Researchers have successfully created a magnetic soliton—a nanosized, spinning droplet that was first theorized 35 years ago. These solitons have implications for the creation of magnetic, spin-based computers. Solitons are waves, localized in space, that preserve their size and momentum. They were first observed in water. Solitons composed of light have proved useful for long-distance, high-speed information transmission. But droplet solitons had never been observed in a magnetic environment, although scientists believed they could exist there.
Kansas State University civil engineers are developing the right mix to reduce concrete's carbon footprint and make it stronger. Their innovative ingredient: biofuel byproducts.
Phototransistors are a kind of transistors in which the incident light intensity can modulate the charge-carrier density in the channel. To date, research on organic phototransistors (OPT) has mostly focused on thin-film variants. Now, researchers in South Korea have developed high-performance OPTs that are engineered with nanoscale single-crystalline wires. The breakthrough could enable other types of device miniaturization.
The search for sustainable new materials to store heat captured from the sun for release during the night has led scientists to a high-tech combination of paraffin wax and sand.
Electrons flowing swiftly across the surface of topological insulators are "spin polarized," their spin and momentum locked. This new way to control electron distribution in spintronic devices makes TIs a hot topic in materials science. Now scientists have discovered more surprises: contrary to assumptions, the spin polarization of photoemitted electrons from a topological insulator is wholly determined in three dimensions by the polarization of the incident light beam.
Researchers at the University of Illinois at Urbana-Champaign have devised a dynamic and reversible way to assemble nanoscale structures and have used it to encrypt a Morse code message. The team started with a template of DNA origami―multiple strands of DNA woven into a tile. They “wrote” their message in the DNA template by attaching biotin-bound DNA strands to specific locations on the tiles that would light up as dots or dashes.
In a world first, a team of researchers from Australia, China, and the U.S. has created a super strong metallic composite by harnessing the extraordinary mechanical properties of nanowires. According to the study’s authors, the work has effectively overcome a challenge that has frustrated the world's top scientists and engineers for more than three decades, nicknamed the "valley of death" in nanocomposite design.
A team of researchers from the National University of Singapore (NUS) has successfully altered the properties of water, making it corrosive enough to etch diamonds. This strange result was achieved by attaching a layer of graphene on diamond and heated to high temperatures. Water molecules trapped between them become highly corrosive, as opposed to normal water.
Germany-based company AMSilk has produced the world’s first competitive man-made spider silk fiber, called Biosteel, which is made entirely from recombinant silk proteins. Biosteel has mechanical properties similar to that of natural spider silk when comparing toughness, a measure indicating the kinetic energy absorbed before the fiber breaks.
A research group at the University of Toronto has recently described a new technique to improve efficiency in what are called colloidal quantum dot photovoltaics. The method depends on a characteristic of quantum dots: Their light-absorption spectrum can be changed simply by changing the size of quantum dot. By adjusting this property to the infrared portion of the spectrum, efficiency is improved.
Working with microscopic artificial atomic nuclei fabricated on graphene, a collaboration of researchers have imaged the “atomic collapse” states theorized to occur around super-large atomic nuclei. This is the first experimental observation of a quantum mechanical phenomenon that was predicted nearly 70 years ago and holds important implications for the future of graphene-based electronic devices.
Chemists at the University of South Florida and King Abdullah University of Science and Technology in Saudi Arabia have discovered a more efficient, less expensive and reusable material for carbon dioxide capture and separation. The highly efficient mechanism utilizes a previously underused material—known as SIFSIX-1-Cu—that attracts carbon atoms.
A multi-university research team has used a new spectroscopic method—energy-momentum spectroscopy—to gain a key insight into how light is emitted from layered nanomaterials and other thin films. The technique lets researchers understand the source and orientation of light in light-emitting thin films and could lead to better LEDs, solar cells, and other devices that use layered nanomaterials.
A new analytical theory has been developed at Purdue University that shows how to design experiments to study ways of controlling dendrite growth on electrodes in lithium-ion batteries. Using this approach, the researchers have shown theoretically how to control or eliminate the formation of these dendrites, which cause lithium-ion batteries to fail. The advance could help improve safety and might enable the batteries to be charged within a matter of minutes instead of hours.
The Fischer-Tropsch process is used for producing fuels from synthesis gas, which in turn is made from natural gas, biomass, or coal. Large reserves of shale or natural gas now changing the world energy market have raised interest in this technology, but prior reactors have been too bulky. Inspired by patents from the 1960s audio cassette recording industry, University of Amsterdam chemists have recently developed a new Fischer-Tropsch catalyst that is significantly cheaper and more scalable.
Until recently, there has been no systematic way of evaluating how different anti-fog coatings perform under real-world conditions. A team of MIT researchers has developed such a testing method, and used it to find a coating that outperforms others not only in preventing foggy buildups, but also in maintaining good optical properties without distortion.
Switchable mirrors can be switched between a transparent state and a mirror state. Some types, which help reduce cooling loads in buildings by blocking sunlight, can be switched electrically. Some can be switch by way of a thin layer of gas that changes mirror properties through hydrogenation. A new type of switchable mirror has been developed in Japan that can control the reflection of visible to near-infrared light at a switching speed about 20 times faster than that of conventional electrochromic switchable glass.
Scientists in Australia are perfecting a technique that may help see nanodiamonds used in biomedical applications. They have been processing the raw diamonds so that they might be used as a tag for biological molecules and as a probe for single-molecule interactions. With the help of an international team, these diamonds have recently been optically trapped and manipulated in three dimensions—the first time this has been achieved.
The salinity difference between freshwater and saltwater could be a source of renewable energy. However, power yields from existing techniques are not high enough to make them viable. A team led by physicists in France has discovered a new means of harnessing this energy. Their method of osmotic flow through boron nitride nanotubes generates electric currents with 1,000 times the efficiency of any previous system.
When a crystal is hit by an intense, ultrashort light pulse, its atomic structure is set in motion. Researchers in Germany have used intensive ultraviolet laser pulses of only a few femtoseconds duration to cause this change in titanium dioxide, a semiconductor. They report that they can observe how the configuration of electrons and atoms changes, confirming that even subtle changes in the electron distribution caused by the excitation can have a considerable impact on the whole crystal structure.
An international team of researchers have recently demonstrated that graphene is able to convert a single photon that it absorbs into multiple electrons that could drive electric current. The experiment sent a known number of photons with different energies onto a monolayer of graphene. In most materials, one absorbed photon generates one electron, but in this case many excited electrons were generated.
In Spiderman 2, the superhero uses his webbing to bring a runaway train to a standstill moments before it plummets over the end of the track. But could a material with the strength and toughness of spiders’ web really stop four crowded subway cars? According to University of Leicester physics students, the answer is yes.
By leaving a dish for a different experiment in the refrigerator, a team of researchers at Washington University in St. Louis has unexpectedly found the mechanism by which tiny single molecules spontaneously grow into centimeter-long microtubes. Their efforts, which evolved into six months of investigation using microscopy and spectroscopy techniques, reveals the self-assembly process of small molecules across multiple length scales.
When gluing things together, both surfaces usually need to be dry. Gluing wet surfaces or surfaces under water is a challenge. Korean scientists have now introduced a completely new concept. They were able to achieve reversible underwater adhesion by using supramolecular "Velcro".
Tiny particles of titanium dioxide are found as key ingredients in common products such as paint and toothpaste. When reduced to the nanoscale, these particle acquire catalytic ability. A team of chemists has recently developed a synthesis to produce these nanoparticles at room temperature in a polymer network. Their analysis has revealed the crystalline structure of the nanoparticles and is a major step forward in the development of polymeric nanoreactors.