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.
Scientists and engineers from an international collaboration have, for the first time, generated and manipulated single particles of light (photons) on a silicon chip. This accomplishment, which required shrinking down key components and integrating them onto a silicon microchip, is a major step forward in the race to build a quantum computer.
Researchers at New York Univ. have developed a method for creating and directing fast moving waves in magnetic fields that have the potential to enhance communication and information processing in computer chips and other consumer products. Their method employs spin waves, which are waves that move in magnetic materials.
Lawrence Livermore National Laboratory researchers have begun to develop a technique that provides a practical approach for looking into the complex physical and chemical processes that occur during fallout formation following a nuclear detonation. Post-detonation nuclear forensics relies on advanced analytical techniques and an understanding of the physio-chemical processes associated with a nuclear detonation to identify the device type.
When a high-altitude aircraft flew over the icy Arctic Ocean and the snow-covered terrain of Greenland in April 2012, it was the first polar test of a new laser-based technology to measure the height of Earth from space. Aboard that aircraft flew the Multiple Altimeter Beam Experimental Lidar, or MABEL, which can resolve elevation change to as little as the width of a pencil.
Using the Robert C. Byrd Green Bank Telescope (GBT), astronomer D.J. Pisano from West Virginia Univ. has discovered what could be a never-before-seen river of hydrogen flowing through space. This very faint, very tenuous filament of gas is streaming into the nearby galaxy NGC 6946 and may help explain how certain spiral galaxies keep up their steady pace of star formation.
Researchers are proposing a new technology that might control the flow of heat the way electronic devices control electrical current, an advance that could have applications in a diverse range of fields from electronics to textiles. The concept uses tiny triangular structures to control phonons, quantum-mechanical phenomena that describe how vibrations travel through a material's crystal structure.
Nearly 30 years after the discovery of high-temperature superconductivity, many questions remain, but an Oak Ridge National Laboratory team is providing insight that could lead to better superconductors. Their work examines the role of chemical dopants, which are essential to creating high-temperature superconductors.
Heralding a new age of terrific timekeeping, a research group led by a NIST physicist has unveiled an experimental strontium atomic clock that has set new world records for both precision and stability—key metrics for the performance of a clock. The JILA strontium lattice clock is about 50% more precise than the record holder of the past few years, NIST’s quantum logic clock.
Do scientific papers written by well-known scholars get more attention than they otherwise would receive because of their authors’ high profiles? A new study co-authored by an Massachusetts Institute of Technology economist reports that high-status authorship does increase how frequently papers are cited in the life sciences—but finds some subtle twists in how this happens.
Researchers in California have made progress in a project to develop fast-blinking light-emitting diode systems for underwater optical communications. They have shown that an artificial metamaterial can improve the “blink speed” of a fluorescent light-emitting dye molecule 76 times faster than normal while increasing brightness 80-fold.