Molecular physicists in The Netherlands have produced images of the changes in direction of colliding nitrogen monoxide molecules (NO) with unprecedented sharpness. By combining a Stark decelerator with advanced imaging techniques, they were able to obtain very high resolution images of the collision processes. The finding sheds light on the wave nature of molecules by imaging what previously had only been theorized.
Engineers are increasingly turning to plasmonic color filters (PCFs) to create and control a broad spectrum of colors for imaging applications. However, PCF light transmission efficiency has been limited to only about 30%, less than half the rate of conventional filters. Researchers have now developed a new PCF scheme that achieves a transmission efficiency of 60 to 70%.
U.S. Army-sponsored researchers have discovered a process for simultaneously storing and dissipating energy within structures that could lead to design rules for new types of active, reconfigurable materials. The study method was derived from an examination of how a species of South American fire ant collectively entangle themselves to form an active structure capable of changing state from a liquid to a solid when subject to applied loads.
Seeking a solution to decoherence, scientists have developed a strategy of linking quantum bits together into voting blocks, a strategy that significantly boosts their accuracy. In a recently published paper, the team found that their method results in at least a five-fold increase in the probability of reaching the correct answer when the processor solves the largest problems tested by the researcher, involving hundreds of qubits.
Topological insulators have been of great interest to physicists in recent years because of unusual properties that may provide insights into quantum physics. But most analysis of such materials has had to rely on highly simplified models. Now, a team of researchers at Massachusetts Institute of Technology has performed a more detailed analysis that hints at the existence of six new kinds of topological insulators.
Lead-free BaTiO3 and KNbO3 ferroelectrics have been known and studied for more than 60 years. However, recent scanning x-ray diffraction studies at Argonne National Laboratory have shown new low-symmetry intermediate phases in these materials that lend a thermotropic character to otherwise well-known phase transitions. The findings show that these transitions in ferroelectrics are closely coupled to the underlying domain microstructure.
Cars inch forward slowly in traffic jams, but molecules, when jammed up, can move extremely fast. New research by Northwestern Univ. researchers finds that water molecules traveling through tiny carbon nanotube pipes do not flow continuously but rather intermittently, like stop-and-go traffic, with unexpected results.
An international team of researchers from France and the United States have devised an entirely new way to synthesize graphene ribbons with defined, regular edges, allowing electrons to flow freely through the material. Demonstrating this phenomenon at room temperature, the material was shown to permit electron flow up to 200 times faster than through silicon.
Texas Advanced Computing Center recently reported the results of several massive numerical simulations charting the forces of the universe in its first hundreds of millions of years. The study, which used some of the world's most powerful supercomputers, has refined our understanding of how the first galaxies formed, and, in particular, how metals in the stellar nurseries influenced the characteristics of the stars in the first galaxies.
We all learn in high school science about the dual nature of light—that it exists as both waves and quantum particles called photons. It’s this duality of light that enables the coherent transport of photons in lasers. Sound at the atomic-scale has the same dual nature, existing as both waves and quasi-particles known as phonons. Does this duality allow for phonon-based lasers?
Using electrons more like photons could provide the foundation for a new type of electronic device that would capitalize on the ability of graphene to carry electrons with almost no resistance even at room temperature—a property known as ballistic transport. Research reported that electrical resistance in nanoribbons of epitaxial graphene changes in discrete steps following quantum mechanical principles.
A team NIST scientists, with collaborators elsewhere, has achieved a five-fold reduction in the dominant uncertainty in an experiment that measured the mean lifetime of the free neutron, resulting in a substantial improvement of previous results. However, the accomplishment reveals a puzzling discrepancy when compared to different method, and researchers are planning to re-run the experiment in upgraded form.
New research shows that a remarkable defect in synthetic diamond produced by chemical vapor deposition allows researchers to measure, witness, and potentially manipulate electrons in a manner that could lead to new “quantum technology” for information processing.
Scientists have used a particle physics theory to describe the behavior of particle-like entities, referred to as excitons, in two layers of graphene. The use of equations typically employed in high-energy physics has prompted the authors to suggest a design for an experimental device relying on a magnetically tunable optical filter that could verify their predictions.
Researchers in the George E. Brown, Jr. Network for Earthquake Engineering Simulation have studied concrete buildings constructed before roughly 1980 in the Los Angeles area. Their work has identified examples of this category of buildings, sometimes referred to as nonductile concrete buildings, which are known from experience in previous earthquakes to have the potential for catastrophic collapse during strong earthquakes.
The same physics that gives tornadoes their ferocious stability lies at the heart of new Univ. of Washington research, and could lead to a better understanding of nuclear dynamics in studying fission, superconductors and the workings of neutron stars. The work seeks to clarify what Massachusetts Institute of Technology researchers witnessed when in 2013 they named a mysterious phenomenon.
The concept of a hypersonic aircraft that takes off from the runway and doesn’t need a rest, inspection or repair is still a unbuilt dream, but Univ. of Cincinnati researchers are developing the validation metrics that could help predict the success or failure of such a model before it is even built, as test data becomes available from component, to sub-system, to the completely assembled air vehicle.
Infrared sensors can be employed in a wide range of applications, such as driver assistance systems for vehicles or thermography for buildings. However, IR detectors need to be permanently cooled, resulting in cameras that are large, heavy and energy-intensive. Researchers are now developing IR sensors for the far-infrared region that can operate at room temperature and a new prototype camera is providing a test bed for development.
Nitrogen molecules travel at a speed of more than 1,700 km/hr at room temperature, which means the particles are much too fast for many experiments and applications. However, physicists have now found a rather simple way to slow down polar molecules to about 70 km/hr: centrifugal force. The new method makes it possible to produce relatively large quantities of cold molecules in a continuous flow.
Calculations and simulations made about a year ago showed for the first time that the thermodynamic flow in an internal combustion engine could be reproduced using individual ions. Scientists in Germany are now working on a heat engine consisting of just a single ion that could be far more efficient than a car engine or a coal-fired power plant.
Scientists at the Univ. of Strathclyde, U.K., have successfully demonstrated two notable high-power laser research developments: the first ever tunable diamond Raman laser and the first continuous-wave (CW) laser. Both lasers use synthetic diamond material made by California’s Element Six. The breakthrough is a significant achievement in solid-state laser engineering.
Only a few elements in the periodic table are inherently magnetic, but scientists have recently discovered that gold, silver, platinum, palladium and other transition metals demonstrate magnetic behavior when formed into nanometer-scale structures. Scientists at the RIKEN Center for Emergent Matter Science have now shown that this nanoscale magnetism in thin films of platinum can be controlled using an externally applied electric field.
By emitting photons from a quantum dot at the top of a micropyramid, researchers at Linköping Univ. in Sweden are creating a polarized light source for such things as energy-saving computer screens and wiretap-proof communications.
Though piezoelectrics are a widely used technology, there are major gaps in our understanding of how they work. Researchers at NIST and in Canada believe they've learned why one of the main classes of these materials, known as relaxors, behaves in distinctly different ways from the rest and exhibit the largest piezoelectric effect. And the discovery comes in the shape of a butterfly.
Plasmonic nanoparticles developed at Rice Univ. are becoming known for their ability to turn light into heat, but how to use them to generate electricity is not nearly as well understood. Scientists at Rice are working on that, too. They suggest that the extraction of electrons generated by surface plasmons in metal nanoparticles may be optimized and have measured the time plasmon-generated electrons take moving from nanorods to graphene.