Researchers from the NIST Center for Nanoscale Science and Technology have observed electromagnetically induced transparency at room temperature and atmospheric pressure in a silicon nitride optomechanical system. This work highlights the potential of silicon nitride as a material for producing integrated devices in which mechanical vibrations can be used to manipulate and modify optical signals.
An international team of scientists has reported the first experimental observation of the quantum critical point (QCP) in the extensively studied “unconventional superconductor” TiSe2, finding that it does not reside as predicted within the superconducting dome of the phase diagram, but rather at a full GPa higher in pressure.
By attaching short sequences of single-stranded DNA to nanoscale building blocks, researchers can design structures that can effectively build themselves. The building blocks that are meant to connect have complementary DNA sequences on their surfaces, ensuring only the correct pieces bind together as they jostle into one another while suspended in a test tube.
Synthetic collagen invented at Rice Univ. may help wounds heal by directing the natural clotting of blood. The material, KOD, mimics natural collagen, a fibrous protein that binds cells together into organs and tissues. It could improve upon commercial sponges or therapies based on naturally derived porcine or bovine-derived collagen now used to aid healing during or after surgery.
In a north London hospital, scientists are growing noses, ears and blood vessels in a bold attempt to make body parts in the laboratory. It's far from the only laboratory in the world that is growing organs for potential transplant. But the London work was showcased this week hints at the availability of more types of body parts, including what would be the world's first nose made partly from stem cells.
Traditionally, scientists discover new materials, and then probe them to understand their properties. Theoretical materials physicist Craig Fennie does it in reverse. He creates new materials by employing a "first principles" approach based on quantum mechanics, in which he builds materials atom by atom, starting with mathematical models, in order to gain the needed physical properties.
Recent experiments in Austria have explained the behavior of electrons at tiny step edges on titanium oxide surfaces. The finding, which shows why oxygen atoms attach so well to these edges, is important for solar cell technology and novel, more effective catalysts.
Researchers at JILA in Colorado have engineered a short, flexible, reusable probe for the atomic force microscope (AFM) that enables state-of-the-art precision and stability in picoscale force measurements. Shorter, softer and more agile than standard and recently enhanced AFM probes, the JILA tips will benefit nanotechnology and studies of folding and stretching in biomolecules such as proteins and DNA.
In steel making, two desirable qualities, strength and ductility, tend to be at odds: Stronger steel is less ductile, and more ductile steel is not as strong. Engineers at Brown Univ., three Chinese universities, and the Chinese Academy of Sciences have shown that when cylinders of steel are twisted, their strength is improved without sacrificing ductility.
Using a new trick, researchers in Germany have been able to induce synchronous motion of the domain walls in a ferromagnetic nanowire. This is an important breakthrough for controlled movement of domain walls that allows permanent data to be stored using nanomagnets. The advance involved applying a pulsed magnetic field that was perpendicular to the plane of the domain walls.
In the fictional Star-Trek universe, the tricorder was used to remotely scan patients for a diagnosis. A new device under development in the U.K. could perform that function through the use of chemical sensors on printed circuit boards. This would replace the current conventional diagnostic method, which is lengthy and is limited to single point measurements.
New research shows that nanostructures could enable more light to be directed into the active layer of solar cells, increasing their efficiency. Prof. Martina Schmid of Freie Univ. in Berlin has measured how irregularly distributed silver particles influence the absorption of light. Nanoparticles interact with one another via their electromagnetic near-fields, so that local “hot spots” arise where light is concentrated especially strongly.
Nanoengineering researchers at Rice Univ. and Nanyang Technological Univ. in Singapore have unveiled a potentially scalable method for making one-atom-thick layers of molybdenum diselenide—a highly sought semiconductor that is similar to graphene but has better properties for making certain electronic devices like switchable transistors and light-emitting diodes.
Materials scientists have long known that introducing defects into 3-D materials can improve their mechanical and electronic properties. Now a new Northwestern Univ. study finds how defects affect 2-D crystalline structures, and the results hold information for designing new materials.
A new theoretical study shows the conductivity conditions under which graphene nanoribbons can become switches in externally controlled electronic devices. The results, obtained by researchers in Argentina and Brazil, yield a clearer theoretical understanding of conductivity in graphene samples of finite size, which have applications in externally controlled electronic devices.
Navy researchers have recently demonstrated sustained flight of a radio-controlled P-51 fighter replica fueled by a new gas-to-liquid process that uses seawater as carbon feedstock. The fuel is made using an innovative and proprietary electrolytic cation exchange module that separates gases from water at 92% efficiency. Catalysis converts the gases to liquid hydrocarbons.
Solid-state dye-sensitized solar cells have shown their potential in achieving high efficiency with a low cost of fabrication. Degradation of these cells shortens lifespan dramatically, however, and the causes of this are not well understood. After a detailed analysis, researchers in Okinawa have determined which material in the cells was degrading, and why.
Chemists have found that cellulose, the most abundant organic polymer on Earth, can be heated in a furnace in the presence of ammonia and turned into the building blocks for supercapacitors. The new process produces nitrogen-doped, nanoporous carbon membranes, which act as the electrodes of a supercapacitor. The only byproduct is methane, which could be used immediately as a fuel or for other purposes.
Carbon nanotubes are reinforcing bars that make 2-D graphene much easier to handle in a new hybrid material grown by researchers at Rice Univ. The Rice laboratory of chemist James Tour set nanotubes into graphene in a way that not only mimics how steel rebar is used in concrete but also preserves and even improves the electrical and mechanical qualities of both.
A combined computational and experimental study of self-assembled silver-based structures known as superlattices has revealed an unusual and unexpected behavior: arrays of gear-like molecular-scale machines that rotate in unison when pressure is applied to them.
A research team has developed a small electronic sensing device that can alert users wirelessly to the presence of chemical vapors in the atmosphere.
As the properties and applications of graphene continue to be explored in laboratories all over the world, a growing number of researchers are looking beyond the one-atom-thick layer of carbon for alternative materials that exhibit similarly captivating properties.
Engineers have demonstrated thin, soft stick-on patches that stretch and move with the skin and incorporate commercial, off-the-shelf chip-based electronics for sophisticated wireless health monitoring.
A medical device, once its job is done, could harmlessly melt away inside a person’s body. Or, a military device could collect and send its data and then dissolve away, leaving no trace of an intelligence mission. Or, an environmental sensor could collect climate information, then wash away in the rain. It’s a new way of looking at electronics.