The transistor of the future may not rely on decreased size, but on a radical change in operation. The device: a quantum mechanical transistor created at Sandia National Laboratories. The transistor corresponds to turning on a light bulb--without closing a switch. With the device, electrons "tunnel" from path to path through a barrier that, according to classical physics, is impenetrable. The process resembles the way cars use a tunnel to reach a location, without having to drive over an impossibly high summit. "We have demonstrated real circuits that work and are easily fabricated," reports Jerry Simmons, leader of the Sandia development team. In the device, two gallium arsenide layers, each only 150 angstroms thick, are separated by a 125-angstrom, aluminum-gallium arsenide barrier. The tiny thickness of the barrier causes the electrons to behave like waves, which can poke into the barrier. The device may run at a trillion operations a second, roughly 10 times the speed of the fastest transistor circuits currently in use. Actual speed has not yet been measured, says Simmons, because it is "not easy to measure such high speeds, which are near the limits of measurements with conventional equipment." E-mail jsimmon@sandia..
The Dutch are known for their love of bicycling, and they’ve also long been early adopters of green-energy and smart-city technologies. So it seems fitting that a town in which painter Vincent van Gogh once lived has given him a very Dutch-like tribute -- a bike path lit by a special smart paint in the style of the artist's “Starry Night” painting.
For decades, engineers have worked to combat erosion by developing high-strength alloys, composites, and surface coatings. However, in a new paper, a team at Jilin University in China turned to one of the most deadly animals in the world for inspiration -- the yellow fat-backed scorpion.
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