Scientists from the U.S. Department of Energy’s National Renewable Energy Laboratory and other labs have demonstrated a process whereby quantum dots can self-assemble at the apex of a gallium arsenide-aluminum gallium arsenide core-shell nanowire interface. This activity at optimal locations in nanowires could improve solar cells, quantum computing, and lighting devices.
Researchers have tried for decades to replicate the effects of transistors in transition metal oxides by using a voltage to convert the material from an insulator to a metal, but the induced change only occurs within a few atomic layers of the surface. Recently, however, scientists in Japan have discovered that applying a voltage to a vanadium dioxide film several tens of nanometers thick converts the entire film from an insulator to a metal.
Organic semiconductors hold promise for making low-cost flexible electronics—if they can perform in spite of frequent flexing and sharp bending. Scientists have recently demonstrated extremely flexible organic semiconductors that withstood multiple bending cycles in which the devices were rolled to a radius as small as 200 μm. The scientists worked with numerous crystalline devices they made and found no degradation in their performance.
Silica microwires are the tiny and as-yet underutilized cousins of optical fibers. If precisely manufactured, however, these hair-like slivers of silica could enable applications and technology not currently possible with comparatively bulky optical fiber. By carefully controlling the shape of water droplets with an ultraviolet laser, a team of researchers from Australia and France has found a way to coax silica nanoparticles to self-assemble into much more highly uniform silica wires.
Existing optical beamsteering assemblies for technologies like LADAR, which scans a field of view with a laser to determine distance, are typically mechnical, bulky, slow, and inaccurate. In an effort to design a better, scalable technology, DARPA researchers have recently demonstrated the most complex optical phased array ever built onto a 2D chip.
High-performance infrared cameras are usual for night-vision goggles and are usually either active, which use invisible infrared sources, or passive, which detect thermal radiation without the need for illumination. Integrating both modes has proven challenging, but researchers at Northwestern University have done by using advanced type-II superlattice materials.
A Massachusetts Institute of Technology researcher has developed a technique that provides a new way of manipulating heat, allowing it to be controlled much as light waves can be manipulated by lenses and mirrors. The approach relies on engineered materials consisting of nanostructured semiconductor alloy crystals.
Silicon carbide crystals consist of a regular lattice formed by silicon and carbon atoms. At present, these semiconductors are extensively used in micro and opto-electronics. Physicists have recently modified silicon carbide crystals in a way that these exhibit new and surprising properties. This makes them interesting with regard to the design of high-performance computers or data transmission.
Investigators at the Virginia Tech Carilion Research Institute have invented a way to directly image biological structures at their most fundamental level and in their natural habitats. Their newly developed in situ molecular microscopy provides a gateway to imaging dynamic systems in structural biology
Inductors are essential components of integrated circuits. The sprawling metal spirals store magnetic energy, acting as a buffer against changes in current and modulating frequency. However, because inductance depends on the number of coils, they take up a lot of space. Researchers have recently build a 3D rolled-up inductor with a footprint more than 100 times smaller without sacrificing performance.
After more than a decade of research, chip engineers at IBM Research have built a scalable, fab-ready microchip that successfully integrates a complete optical package built from silicon. This silicon nanophotonics breakthrough allows the new chip, which is built on an existing high-performance 90-nm CMOS fabrication line, to exceed a transceiver data rate of 25 Gbps per channel.
Silicon's crown is under threat: The semiconductor's days as the king of microchips for computers and smart devices could be numbered, thanks to the development of the smallest transistor ever to be built from a rival material, indium gallium arsenide. The compound transistor, built by a team at Massachusetts Institute of Technology, performs well despite being just 22 nm in length.
For the first time, a silicon-based optical fiber with solar cell capabilities has been developed that has been shown to be scalable to many meters in length. The research opens the door to the possibility of weaving together solar cell silicon wires to create flexible, curved, or twisted solar fabrics.
Electronic circuits are typically integrated in rigid silicon wafers, but flexibility opens up a wide range of applications. In a world where electronics are becoming more pervasive, flexibility is a highly desirable trait, but finding materials with the right mix of performance and manufacturing cost remains a challenge. Now a team of researchers from the University of Pennsylvania has shown that nanocrystals of the semiconductor cadmium selenide can be "printed" or "coated" on flexible plastics to form high-performance electronics.
Synchrotron-based imaging has helped develop enhanced light-emitting diode (LED) displays using bottom-up engineering methods. Collaborative work between researchers from the University of Florida and Cornell University has produced a new way to make colloidal "superparticles" from oriented nanorods of semiconducting materials.
University of California, Davis researchers, for the first time, have looked inside gallium manganese arsenide, a type of material known as a "dilute magnetic semiconductor" that could open up an entirely new class of faster, smaller devices based on an emerging field known as spintronics.
NIST announced the selection of the Nanoelectronics Research Initiative (NRI), a collaboration of several key firms in the semiconductor industry, to support university-centered research for the development of after-the-next-generation "nanoelectronics" technology. NRI consists of participants from the semiconductor industry, including GLOBALFOUNDRIES, IBM, Intel, Micron Technology, and Texas Instruments.
Thanks to an ultrasensitive accelerometer—a type of motion detector—developed by researchers at the California Institute of Technology and the University of Rochester, a new class of microsensors is a step closer to reality. Instead of using an electrical circuit to gauge movements, this accelerometer uses laser light and is so sensitive it could be used to navigate shoppers through a grocery aisle or even stabilize fighter jets.
Using a new technique called HARPES, for hard X-ray angle-resolved photoemission spectroscopy, Lawrence Berkeley National Laboratory researchers have unlocked the ferromagnetic secrets of dilute magnetic semiconductors, materials of great interest for spintronic technology.
Researchers from North Carolina State University have created flower-like structures out of germanium sulfide (GeS)—a semiconductor material—that have extremely thin petals with an enormous surface area. The GeS flower holds promise for next-generation energy storage devices and solar cells.
A research team in Japan has succeeded in developing equipment that enables simple, high speed measurement of the band diagrams of organic semiconductor materials in atmospheric conditions. The device essentially combines a spectrophotometer system for studying band gaps with a photoemission yield system to examine ionized potential.
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.
Silicon is used in components, e.g. filters or deflectors, for telecommunications. So far, however, all these components have been flat, or 2D. Researchers have developed a new etching method for these structures that results 3D microstructures in silicon. Suitable for fiber optic communications, their optical properties are adjustable at the micrometer scale.
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.
University of Illinois researchers have a new, low-cost method to carve delicate features onto semiconductor wafers using light—and watch as it happens. The researchers' new technique can monitor a semiconductor's surface as it is etched, in real time, with nanometer resolution, using a special type of microscope that uses two beams of light to precisely measure topography.