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Tiny semiconductor dots could lead to a new type of circuit based on magnetism rather than current flow. At least that’s the hope of researchers who’ve made the dots and are hoping to build them into a workable device. ”We want to make it into a so-called nonvolatile transistor,” says Kang Wang, head of the Device Research Laboratory at the University of California, Los Angeles. Such a ”spintronic” transistor would retain its logic state in the absence of current and require less power to switch a bit, reducing the electrical power required by a computer chip by as much as 99 percent. Wang’s research, supported in part by Intel, was published in March in the online version of Nature Materials. Where electronic transistors rely on the presence or absence of current to register the ones and zeros of digital logic, spintronic transistors depend on ”spin,” a quantum characteristic of the electron. Picture the electron as a rotating globe. When the north pole is pointing upward, that’s spin up; when pointing the other way, it’s spin down. When the spins of most electrons are aligned, the material is magnetic. When their spins are random, the material isn’t. An applied current can align or randomize the spins, allowing for spin-based switches.

A transistor that emits light and is made from organic materials could lead to cheaper digital displays and fast-switching light sources on computer chips, according to the researchers who built it. Small displays made from diodes of the same type of materials (organic light-emitting diodes, or OLEDs) are already in commercial production, but the transistor design could improve on those and lead to applications where OLEDs can’t go. The new organic light-emitting transistor (OLET) is much more efficient than previous designs. It has an external quantum efficiency—a key measure of how much light comes out per charge carrier pumped in—of 5 percent. An OLED based on the same material has a quantum efficiency of only 2 percent. Previous OLET designs had an efficiency of only 0.6 percent.

Events such as natural disasters, military actions, and public safety threats have led to an increased need for robust robots — especially ones that can travel across complex terrain in any dimension. The ability to scale vertical building surfaces or other structures offers unique capabilities in military applications such as urban reconnaissance, sensor deployment, and setting up urban network nodes. SRI's novel clamping technology, called compliant electroadhesion, has enabled the first application of this technology to wall-climbing robots that can help with these situations.  As the name implies, electroadhesion is an electrically controllable adhesion technology. It involves inducing electrostatic charges on a wall substrate using a power supply connected to compliant pads situated on the moving robot. SRI has demonstrated robust clamping to common building materials including glass, wood, metal, concrete, etc. with clamping pressures in the range of 0.5 to 1.5 N per square cm of clamp (0.8 to 2.3 pounds per square inch). The technology works on conductive and non-conductive substrates, smooth or rough materials, and through dust and debris. Unlike conventional adhesives or dry adhesives, the electroadhesion can be modulated or turned off for mobility or cleaning. The technology uses a very small amount of power (on the order of 20 microwatts/Newton weight held) and shows the ability to repeatably clamp to wall substrates that are heavily covered in dust or other debris.

The potential for the QTC material to transition from an insulator to a conductor (i.e. change its electrical property) is influenced by how much deformation the material is experiencing as a result of the applied mechanical pressure. QTC can be used to produce low profile, low cost, pressure activated switches or sensors that display variable resistance with applied force and return to a quiescent state when the force is removed. The difference between a QTC switch and a QTC sensor is arguably only the speed and amount of physical input required to achieve the required switching point or resistance range.

The science behind gecko toes holds the answer to a dry adhesive that provides an ideal grip for robot feet. Stanford mechanical engineer Mark Cutkosky is using the new material, based on the structure of a gecko foot, to keep his robots climbing.

Single-walled carbon nanotube (SWCNT)-based thin film transistors (TFTs) could be at the core of next-generation flexible electronics – displays, electronic circuits, sensors, memory chips, and other applications that are transitioning from rigid substrates, such as silicon and glass, to flexible substrates. What's holding back commercial applications is that industrial-type manufacturing of large scale SWCNT-based nanoelectronic devices isn't practical yet because controlling the morphology of single-walled carbon nanotubes is still causing headaches for materials engineers.

In 2008 a team of physicists from Argonne National Laboratory, in Illinois, and other institutions stumbled upon an odd phenomenon. They called it superinsulation, because in many ways it was the opposite of superconductivity. Now they’ve worked out the theory behind it, potentially opening the doors to better batteries, supersensitive sensors, and strange new circuits. Superconductors lose all resistance once they fall below a certain temperature. In superinsulators, on the other hand, the resistance to the flow of electricity becomes infinite at very low temperatures, preventing any flow of electric current.

Just as photographic film was mostly replaced by silicon image chips, now quantum film threats to replace the conventional CMOS image sensors in digital cameras. Made from materials similar to conventional film—a polymer with embedded particles—instead of silver grains like photographic film the embedded particles are quantum dots. Quantum films can image scenes with more pixel resolution, according to their inventors, InVisage Inc., offering four-times better sensitivity for ultra-high resolution sensors that are cheaper to manufacture.

One of the biggest commercial applications of spintronics in computing to date has been the use of giant magnetoresistance (GMR), the material phenomenon that makes possible the huge storage capacity of today’s hard disk drives. In the awarding of the 2007 Nobel Prize in Physics, GMR was cited as the first big commercial application for nanotechnology. But extending the commercial application of spintronic-enabled systems beyond read heads for HDDs has proven to be a difficult task. One need only look at the seemingly endless travails of NVE Corporation, which in its financial results still shows it greatest revenue growth in contract research as opposed to product sales. While recent research from a team of researchers at Ohio State University and the University of Hamburg in Germany may not turn around the fortunes of spintronics in the short term, it does provide a way to better characterize the spin of electrons and thereby promises better ways of exploiting it for electronics applications. The researchers are reporting in Nature Nanotechnology that they have for the first time been able to create images of the spin direction of electrons.