Particle counters are used in a wide variety of industries. Researchers in North Carolina have developed a new thermal technique that counts and measures the size of particles, but is less expensive than light-based techniques. It can also be used on a wider array of materials than electricity-based techniques.
Researchers have discovered that creating a graphene-copper-graphene “sandwich” strongly enhances the heat conducting properties of copper, a discovery that could further help in the downscaling of electronics.
Will one-atom-thick layers of molybdenum disulfide, a compound that occurs naturally in rocks, prove to be better than graphene for electronic applications? Recent research into phenomena occurring in the crystal network of this material show signs that might prove to be the case. But physicists in Poland have shown that the nature of the phenomena occurring in layered materials are still ill-understood.
Researchers have applied a novel microscopy technique to characterize metal-organic framework (MOF) materials, potentially opening a pathway for engineering the chemical properties of these materials at the nanoscale. MOFs are composed of metal ions connected by organic linker molecules to form 3-D-crystalline networks of nanopores with high surface areas, leading to applications in catalysis, chemical separation and sensing.
Thin films of spin ice have been shown to demonstrate surprising properties which could help in the development of applications of magnetricity, the magnetic equivalent of electricity. Researchers based at the London Centre for Nanotechnology, in collaboration with scientists from Oxford and Cambridge, found that, against expectations, the Third Law of Thermodynamics could be restored in thin films of the magnetic material spin ice.
Using little more than a few perforated sheets of plastic and a staggering amount of number crunching, Duke Univ. engineers have demonstrated the world’s first 3-D acoustic cloak. The new device reroutes sound waves to create the impression that both the cloak and anything beneath it are not there.
Graphene is not the only ultrathin material that exhibits special electronic properties. Ultrathin layers made of tungsten and selenium have recently been created in Austria that show a high internal efficiency when used to gather sunlight. More than 95% of light passes straight through, but a tenth of what is stopped is converted to electricity.
A team of Massachusetts Institute of Technology researchers has used a novel material that’s just a few atoms thick to create devices that can harness or emit light. This proof-of-concept could lead to ultra-thin, lightweight and flexible photovoltaic cells, light-emitting diodes (LEDs) and other optoelectronic devices, they say.
Experts from the Univ. of Buffalo (UB), helped by colleagues from two Chinese universities, have developed an optical "nanocavity" that could help increase the amount of light absorbed by ultrathin semiconductors. The advancement could lead to the creation of more powerful photovoltaic cells and improvements in video cameras and even hydrogen fuel, as the technology could aid the splitting of water using energy from light.
A new mechanism of controlling magnetic states by electric currents has been discovered by an international team of researchers who have exploited a quantum phenomenon to control magnetic states with electrical currents. The research hinges on a quantum geometrical phase, called the Berry phase, that exists in the momentum space of electronic band structures in specific materials.
Flawed but colorful diamonds are among the most sensitive detectors of magnetic fields known today, allowing physicists to explore the minuscule magnetic fields in metals, exotic materials and even human tissue. A team of physicists have now shown that these diamond sensors can measure the tiny magnetic fields in high-temperature superconductors, providing a new tool to probe these much ballyhooed but poorly understood materials.
Researchers from Empa and ETH Zurich have succeeded in producing a prototype of a vibration-damping material that could change the world of mechanics. The material of the future is not only able to damp vibrations completely; it can also specifically conduct certain frequencies further.
The huge surface area and strong interactions between graphene layers causes facile “stacking” behavior that dramatically reduces available surface area, inhibiting graphene electronic properties. Researchers have tried to prevent this with carbon black, but this also carries undesirable property changes. By introducing protuberances on graphene during synthesis, researchers in China have found a solution to the stacking problem.
In physics, there's small, and then there's nullity, as in zero-dimensional. Univ. of Cincinnati researchers have reached this threshold with a special structure, zero-dimensional quantum dots, that may someday lead to better ways of harnessing solar energy, stronger lasers or more sensitive medical diagnostic devices.
Scientists at Los Alamos National Laboratory are working toward even stronger and more elastic glass types which would fail in a ductile fashion instead of shattering. Researchers there are looking at the initiation of shear-banding events in order to better understand how to control the mechanical properties of these materials.
A key to realizing commercial-scale artificial photosynthesis technology is the development of electrocatalysts that can efficiently and economically carry out water oxidation reaction that is critical to the process. Heinz Frei, a chemist Lawrence Berkeley National Laboratory, has been at the forefront of this research effort. His latest results represent an important step forward.
Current technologies for writing, storing, and reading information are either charge-based or spin-based. The downside is that weak perturbations such as impurities or radiation can lead to uncontrolled charge redistributions and, as a consequence, to data loss. Researchers in Europe have predicted and discovered a new physical phenomenon that allows them to manipulate the state of a magnet by electric signals and eliminate this loss.
According to recent findings by an international team of computer engineers, optical data storage does not require expensive magnetic materials because synthetic alternatives work just as well. The team’s discovery that synthetic ferrimagnets can be switched optically brings a much cheaper method for storing data using light a step closer.
Scientists at Ames Laboratory are revealing the mysteries of new materials using ultra-fast laser spectroscopy. Researchers recently used ultra-fast laser spectroscopy to examine and explain the mysterious electronic properties of iron-based superconductors. Seeing these dynamics is one emerging strategy to better understanding how these new materials work.
U.K. scientists have succeeded in measuring how the surfaces of glassy materials flow like a liquid, even when they should be solid. A series of simple and elegant experiments were the solution to a problem that has been plaguing condensed matter physicists for the past 20 years. The finding has implications for thin-film coating designs.
A team of researchers has developed a material that could help prevent blood clots associated with catheters, heart valves, vascular grafts and other implanted biomedical devices. Blood clots at or near implanted devices are thought to occur when the flow of nitric oxide, a naturally occurring clot-preventing agent generated in the blood vessels, is cut off. When this occurs, the devices can fail.
A big step in the development of advanced fuel cells and water-alkali electrolyzers has been achieved with the discovery of a new class of bimetallic nanocatalysts that are an order of magnitude higher in activity than the target set by the U.S. Department of Energy for 2017. The new catalysts feature a 3-D catalytic surface activity that makes them significantly more efficient and far less expensive than the best platinum catalysts.
Ultraviolet light (UV) has not only harmful effects on molecules and biological tissue like human skin but it also can impair the performance of organic solar cells upon long-term exposure. Researchers in Germany have now developed a so-called plasmonic metamaterial which is compatible with solar technology and completely absorbs UV light despite being only 20 nm thin.
How heat flows at the nanoscale can be very different than at larger scales, and researchers are working to understand how these features affect the transport of the fundamental units of heat, called phonons. At Cornell Univ. scientists have invented a phonon spectrometer whose measurements are 10 times sharper than standard methods. This boosted sensitivity has uncovered never-before-seen effects of phonon transport.
Cornell Univ. researchers have recently led what is probably the most comprehensive study to date of block copolymer nanoparticle self-assembly processes. The work is important, because using polymers to self-assemble inorganic nanoparticles into porous structures could revolutionize electronics.