When stretched, a layer of silicon can build up internal mechanical strain which can considerably improve its electronic properties. Using this principle, engineers have developed a method which allows them to produce 30-nm-thick highly strained wires in a silicon layer. This strain is the highest that has ever been observed in a material which can serve as the basis for electronic components.
The ability to determine the composition and physics of nanoscale materials and devices at NIST is about to improve dramatically with the arrival of a new near-field scanning microwave microscope (NSMM) design. Researchers there, using existing commercial and homemade NSMMs, have pioneered many applications, notably including determination of semiconductor dopant distribution in 2D and 3D. Now they hope to look at mechanical and magnetic resonance on the nanoscale.
Optical force refers to the way beams of light can be made to attract or repel each other, as magnets do. Researchers at Missouri University of Science and Technology, in a study that gauged this type of force at the nanoscale, report that a new class of nanoscale slot waveguides pack 100 to 1,000 times more transverse optical force than conventional silicon slot waveguides.
Within optical microchips, light finds its way through waveguides made of silicon, and is amplified with the help of other semiconductors, such as gallium arsenide and erbium. But until recent work in The Netherlands, no chip existed on which both silicon and erbium-doped material had been successfully integrated. The new chip now amplifies light up to 170 Gbit/sec.
Belgium-based semiconductor manufacturing firm imec announced Tuesday that it has integrated an ultra-thin, flexible chip with bendable and stretchable interconnects into a package that adapts dynamically to curving and bending surfaces. The resulting circuitry can be embedded in medical and lifestyle applications where user comfort and unobtrusiveness is key, such as wearable health monitors or smart clothing.
As part of their investigation of the effects ionizing radiation has on crystalline structures found in single-walled carbon nanotube transistors, U.S. Naval Research Laboratory engineers have recently shown these devices can stand up harsh space environments. This durability has been achieved through a combination of a hardened dielectric material and the natural isolation of the transistor.
An international team of scientists has discovered a new class of materials that could prove to be useful in developing new methods of creating computer memory. The research team explored layered heterostructures at the atomic scale, in which different materials were deposited in layers a few atoms thick. They discovered that the new class of materials boasts an attractive property—ferroelectricity.
Probe storage devices read and write data by making nanoscale marks on a surface through physical contact, but they currently have limited lifespans due to mechanical wear. A research team, led by Intel Corp., has now developed a long-lasting ultrahigh-density probe storage device by coating the tips of the probes with a thin metal film. The technology may one day extend the data density limits of conventional magnetic and optical storage.
Stresses arise in thin films during the manufacture of read heads in hard drives, lasers, and computer chip transistors. This can cause crystal lattice defects and eventual component failure. Researchers have recently determined that enormous stresses, up to 1,000 times atmospheric pressure, can be created in thin films by a quantum-mechanical mechanism that has been unknown until now. It is based on an effect by the name of quantum confinement.
An invisible quick response (QR) code has been created by researchers in South Dakota in an attempt to increase security on printed documents and reduce the possibility of counterfeiting, a problem which costs governments and private industries billions of dollars each year. The QR code is made of tiny nanoparticles that have been combined with blue and green fluorescence ink, which is invisible until illuminated with laser light.
Scientists at the Norwegian University of Science and Technology report they have patented and are commercializing gallium arsenide (GaAs) nanowires grown on graphene. These semiconductors, which are being developed for market by the the company CrayoNano, are grown on atomically-thin graphene using molecular beam epitaxy.
Researchers have developed a new kind of anti-theft system, based on a woven fabric, that triggers an alarm when penetrated. Because of the fine lattice of conductive threads woven into the material, the fabric can notify the precise location of a failure, allowing the source of a break-in to be quickly identified. The invention could be significantly cheaper than other burglary detection systems.
For several years, experts in nanotechnology have suspected—but not proven—that quantum interference effects make the conductance of a circuit with two paths up to four times higher than the conductance of a circuit with a single path. By constructing their own controllable, molecular-scale circuits, scientists at Brookhaven National Laboratory have confirmed an increase in conductance. But not as large as was anticipated.
Engineers at Cornell University have invented a way to pattern single atom films of graphene and boron nitride, an insulator, without the use of a silicon substrate. The technique, called patterned regrowth, is reliant on conventional silicon photolithography technology and could lead to substrate-free circuits that would be atomically thin yet retain high tensile strength and superior electrical performance.
In attempt to achieve better control of heat flows in electronic devices, a researcher in Finland has invented two new mesoscopic devices based on the behavior of single electrons in a constructed system. The inventions, which include a diode, or rectifier, specifically address the heat carried by an electron and help produce a strongly asymmetric heat flow. The next step will be to manage larger currents.
Flat panel displays and mobile phones require thin, efficient, and low-cost light emitters, which are typically made from pixels wired to complex electronic circuits. Engineers in Singapore have now developed a display technology that requires a much simpler architecture: a thin perforated gold film with a liquid crystal layer.
A critical element in any microchip is an inverter—an electronic component that spits out zeros when it is given ones, and vice versa. Complementary metal-oxide-semiconductor, or CMOS, is the industry standard for this type of component, but still requires billions of dollars to achieve production scale. Researchers have recently pioneered a room-temperature additive process that creates a nanoscale inverter quickly and at low cost.
A team of organic chemists have discovered they can create very long crystals with desirable properties using just two small organic molecules that are extremely attracted to each other. The attraction between the two molecules causes them to self assemble into an ordered network, and, most importantly, they possess the ferroelectric properties that are useful in computing.
After making a sheet of “paper” from the world’s thinnest material, graphene, Rensselaer Polytechnic Institute scientists zapped it with a laser. The light blemished the ultrathin paper with countless cracks, pores, and other imperfections. The result is a graphene anode material that can be charged or discharged 10 times faster than conventional graphite anodes used in today’s lithium-ion batteries.
A team of researchers at in Japan has demonstrated a new material that promises to eliminate loss in electrical power transmission. Their methodology for solving this classic energy problem is based on a highly exotic type of magnetic semiconductor first theorized less than a decade ago—a magnetic topological insulator.
Scientists in Sweden report they have produced organic light-emitting electrochemical cells (LECs) using a roll-to-roll compatible process under ambient conditions. They say the innovation proves that LECs can be produced as inexpensive and thin, large-area light-emitting devices for informative displays and, at a later stage, lighting applications.
Researchers from two SLAC-Stanford University joint institutes recently joined forces to investigate a catalyst that promotes energy-releasing reactions in fuel cells. What they discovered, after using high-resolution X-ray spectrometry, is that two different platinum-rhodium nanostructures behaved in strikingly different ways. The finding indicated the importance of careful engineering in catalyst design.
Scientists at IBM Research and ETH Zurich in Switzerland report that they are the first to synchronize electron spins and image the formation of a persistent spin helix in a semiconductor. Until now, it was unclear whether electron spins could preserve encoded information long enough before rotating. This new work extends spin lifetime 30-fold, to 1.1 nanosec.
Multiferroics are expected to be applied to a new type of memory devices in which dielectric polarization is controlled by a magnetic field and magnetization is controlled by an electric field. However, multiferroic materials that function at room temperature are rare. In a breakthrough toward this goal, a team in Japan and the U.K. have achieved ferroelectric polarization without a magnetic field after discovering that they could swap out atoms and still maintain control of the multiferroic’s dielectric and magnetic properties.
Researchers at Argonne National Laboratory and in Switzerland have recently demonstrated the existence of long-lived charge-separated states in silver clusters. The stable charge-separated state, together with the fact that the clusters absorb light over a wide range of wavelengths, mean that the clusters represent a new and promising class of materials for solar energy applications.