electricity
Engineers have designed a new diode that transmits more electricity than any other device of its kind, and the inspiration for it came from technology that is 40 years old. Unlike other diodes in its class, called tunnel diodes, the new diode is compatible with silicon, so manufacturers could easily build it into mainstream electronic devices such as cell phones and computers.
You can't get something for nothing, physicists say, but sometimes a radical innovation can come close. Researchers at Sandia National Laboratories -- exceeding the predictions of a 100-year-old law of physics -- have shown that filaments fabricated of tungsten lattices emit remarkably more energy than solid tungsten filaments in certain bands of near-infrared wavelengths when heated. This greater useful output offers the possibility of a superior energy source to supercharge hybrid electric cars, electric equipment on boats, and industrial waste-heat-driven electrical generators. The lattices' energy emissions put more energy into wavelengths used by photovoltaic cells that change light into electricity to run engines.
Scientists at Research Triangle Institute in North Carolina have created the world?s first working device that uses nanometer-scale materials to convert electric power into cooling or heating, or heat into electricity. Among its many potential applications, the development could eventually lead to more reliable solid-state refrigerators and air conditioners, and more efficient and compact power sources, according to the researchers.
In his State of the Union address, President Bush announced a $1.2 billion Freedom Fuel initiative to reverse America?s growing dependence on foreign oil by developing the technology for commercially viable hydrogen-powered fuel cells to power cars, trucks, homes and businesses with no pollution or greenhouse gases. The Freedom Fuel initiative will include $720 million in new funding over the next five years to develop the technologies and infrastructure to produce, store, and distribute hydrogen for use in fuel cell vehicles and electricity generation. Combined with the FreedomCAR (Cooperative Automotive Research) initiative, President Bush is proposing a total of $1.7 billion over the next five years to develop hydrogen-powered fuel cells, hydrogen infrastructure and advanced automotive technologies.
Scientists have discovered superconductivity in a most unlikely place: the highly radioactive element used to make nuclear weapons. In an article set to appear Thursday in the journal Nature, a group of researchers, including a University of Florida physicist, report discovering a plutonium-based electrical superconductor. The finding is significant because plutonium, the active ingredient in atomic bombs, has physical properties that should prevent it from behaving as a superconductor - suggesting current theories about this phenomenon may not apply to this element.
Researchers have found that the electrical properties of the semiconductor indium nitride are different from what been previously thought -- by a wide margin. The result is that an alloy incorporating the material can convert virtually the full spectrum of sunlight -- from the near infrared to the far ultraviolet -- to electrical current. "It's as if nature designed this material on purpose to match the solar spectrum," said one researcher involved.
Aluminum -- one of nature's best conductors of electricity conductors of electricity -- may behave like a ceramic or a semiconductor in certain situations, according to an Ohio State University scientist and his colleagues. Among the findings that appear in the current issue of the journal Science: When it comes to forming tiny structures in computer chip circuits and nanotechnology, aluminum may endure mechanical stress more than 30 percent better than copper, which is normally considered to be the stiffer metal
The New York Times and the Associated Press take long looks at flip sides of the coming Intel-Advanced Micro Devices war over 64-bit processors. In "Intel's Huge Bet Turns Iffy," The Times examines the company's enormous investment of time and money --- 10 years and $5 billion --- into the chip, which it co-developed with Hewlett-Packard. The Infineon, or more precisely the Infineon 2 (an earlier version 1 was largely considered a flop) handles enormous quantities of data, but also uses lots of electricity. While the former is nice, the Times says, companies that run big server farms are increasingly mindful about all the juice needed to keep them running and cooled. AMD's own 64-bit entry, the Hammer, uses less electricity, the Times notes ominously. But as the AP reports, there are no guarantees for AMD either. One of Hammer's big selling points is that it is backward compatible with current x86 software, meaning anything you're running now on a Windows box and more. That could make it an appealing crossover product, tempting for use in corporate servers and consumer desktops alike. But with a soft economy and many people happy with the speed they've already got, anything short of a groundswell adoption could be a major bummer for the perennial no. 2.
Intel is set to disclose some of its plans in nanotechnology, sure to be key to the company's chips for decades to come. As reported by CNET's News.com, Sunlin Chou, senior VP of technology and manufacturing, will discuss some of the plans next week at the Intel Developer Forum in San Jose. Topping the topics likely to be covered: Carbon nanotubes and multigate transistors. Nanotubes are strings of carbon atoms tightly bonded together that show promise in manufacturing everything from tennis rackets to electronics. In computer chips, they can theoretically be used to replace the wispy metal wires that now define a chip's circuitry. That could make processors smaller and cheaper. Multigate transistors, meanwhile, are a way of addressing the conundrum faced by all chipmakers: The more powerful processors become, the more electricity must flow through them. But as chips shrink in size, the extremely small transistors that control this flow are growing overloaded, something like hooking up a fire hose to a Waterpik nozzle, as CNET puts it. One way around that is to give each transistor more than one gate, an approach that IBM is using in some of its products already. Although analysts say they doubt Intel will copy this entirely, the company likely has a similar approach up its sleeve.
The Associated Press reports materials researchers have begun experimenting with chicken feathers and soy resin to craft future computer processors. Researchers in the University of Delaware's ACRES program --- Affordable Composites from Renewable Sources --- looked to chicken feathers because they have shafts that are hollow but strong, and made mostly of air, which is a great conductor of electricity. The feathers and resin are crafted into a composite material that looks and feels like silicon, according to program director Richard Wool. In initial tests, electric signals moved twice as fast through the organic chip as through a silicon chip, researchers said. "The first time, Dr. Wool's response was, 'Recheck,'" said post-doc Chang Kook Hong, who headed the research. "I repeated the test three times with the same results. Then he said, 'You have a hit here.'" Don't expect feather Pentiums any time soon, however. The natural bumps and irregularities that come from using an organic base are a big impediment to commercial use. "The microchip industry depends on materials that are ultrasmooth and ultraflat," said one researcher. "This was anything but that."
